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Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics (2011)

Chapter: 7 Report of the Panel on Optical and Infrared Astronomy from the Ground

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Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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7
Report of the Panel on Optical and Infrared Astronomy from the Ground

SUMMARY

The celebration of the 400th anniversary of Galileo’s first use of an astronomical telescope provides a fitting context for planning new goals and directions for ground-based optical and infrared (OIR) astronomy in the 21st century. The revolutionary improvement over the unaided eye that Galileo’s telescope provided in angular resolution and sensitivity began a transformation and expansion of our knowledge of the universe that continues to this day. The OIR ground-based projects and activities recommended for the 2010-2020 decade are the next step that will open up unprecedented capabilities and opportunities, ranging from discovery in our solar system and the realms of exoplanets and black holes to understanding of the earliest objects in the universe and the foundations of the cosmos itself.

The vital science carried out by optical and infrared telescopes on Earth is at the core of the challenging astrophysics program laid out by the Astro2010 Science Frontiers Panels (SFPs). With the federal support recommended in this report by the Program Prioritization Panel on Optical and Infrared Astronomy from the Ground (the OIR Panel) for the construction of a Giant Segmented Mirror Telescope (GSMT), the Large Synoptic Survey Telescope (LSST), the development of ever-more-capable and technically advanced instrumentation, and renewed strategic stewardship of the nation’s suite of telescopes, the United States will maintain a leading role in the pursuit of science that probes to the farthest corners of the known universe. With the generation of extremely large and rich data sets, the system of telescopes and facilities envisioned will continue the transformation of

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

astrophysical research. They will build on the success of programs identified by previous decadal surveys and lay the foundations for astronomical research far beyond 2020 by supporting the next generation of telescopes for which the astronomical community has been planning and preparing over the past two decades.

This panel recommends new programs to optimize science opportunities across astronomy and astrophysics in ways that will support work at all scales: from the inspired individual to teams of hundreds of astronomers and billion-dollar projects. These recommendations combine to reinvigorate the U.S. system of OIR telescopes and facilities, heralding a new, expanded era of federal and nonfederal partnership for astronomical exploration.1

The Astro2010 survey occurs at a time of great challenge and great opportunity for OIR astronomy in the United States, which has led the world for the past century. In addition to the technical and intellectual challenges of OIR research, Europe, through its European Southern Observatory, is achieving parity with the United States in telescopes with apertures greater than or equal to 6 m and is poised to take a leading position with its plans for a 42-m Extremely Large Telescope project. The opportunity exists for U.S. OIR astronomy to marshal and coordinate its great resources and creativity and build on its successes and accomplishments to answer the fundamental questions posed by Astro2010.

Large Projects

The frontiers of astronomy and astrophysics have been advanced over the course of the 20th century, starting with the Mount Wilson 60-inch (1.5-m) telescope in 1908, by each decade’s suite of ever-more-capable OIR telescopes and instruments. Continuing into the 21st century, the science opportunities in the coming decade promise to be equally great, as the OIR community stands ready to build the next generation of facilities.

A GSMT, with a collecting area exceeding 100 times that of the Hubble Space Telescope and with a 10-times-better angular resolution, will open up discovery space in remarkable new directions, probe dense environments within the Milky Way and in nearby galaxies, and—coupled with advanced adaptive optics (AO)—will map planetary systems around nearby stars. A GSMT’s capabilities for astrometry will offer an unparalleled ability to probe the kinematics of galaxies, stars, and planets at the very highest angular resolution, offering sensitivities that are, in some

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The previous decadal survey—Astronomy and Astrophysics in the New Millennium (AANM; National Academy Press, Washington, D.C., 2001)—advocated a system perspective toward the sum of all U.S. OIR facilities in order to encourage collaborations between federally funded and independent observatories so that federal funds would be leveraged by private investment. The system today is an emerging network of public and private ground-based observatories with telescopes in the 2- to 10-m-aperture range.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

cases, almost 10 magnitudes better than that achievable in space in the next decade. With a suite of spectroscopic and imaging instrumentation covering the optical and near-infrared (IR) bands, GSMT will be crucial for detailed follow-up investigations of discoveries from existing and planned facilities, including the James Webb Space Telescope (JWST) and the Atacama Large Millimeter Array (ALMA).

The promise of the next decade lies also in the capability of building a telescope to conduct systematic, repeated surveys of the entire available sky to depths unobtainable before now. Combining repeated survey images will provide composite wide-field images extending more than 10-fold fainter. Readily available synoptic data will revolutionize investigations of transient phenomena, directly addressing the key discovery area of time-domain astronomy, as well as being invaluable in surveys of regular and irregular variable sources, both galactic and extragalactic. At the same time, the combined images will provide a multi-waveband, homogeneous, wide-field imaging data set of unparalleled sensitivity that can be used to address a wide range of high-impact scientific issues. As the 48-inch Schmidt Telescope did with respect to the 200-inch Palomar Observatory, so also will LSST play a fundamental role in detecting the most fascinating astronomical targets for follow-up observations with GSMT.

Having considered proposals from the research community for new large facilities, the panel’s conclusions with respect to large projects are as follows:

  • The science cases for a 25- to 30-m Giant Segmented Mirror Telescope and for the proposed Large Synoptic Survey Telescope are even stronger today than they were a decade ago.

  • Based on the relative overall scientific merits of GSMT and LSST, the panel ranks GSMT higher scientifically than LSST, given the sensitivity and resolution of GSMT.

  • Both GSMT and LSST are technologically ready to enter their construction phases in the first half of the 2010-2020 decade.

  • The LSST project is in an advanced state and ready for immediate entry into the National Science Foundation’s (NSF’s) Major Research Equipment and Facilities Construction (MREFC) line for the support of construction. In addition, the role of the Department of Energy (DOE) in the fabrication of the LSST camera system is well defined and ready for adoption.

  • LSST has complementary strengths in areal coverage and temporal sensitivity, with its own distinct discovery potential. Indeed, GSMT is unlikely to achieve its full scientific potential without the synoptic surveys of LSST. Consequently, LSST plays a crucial role in the panel’s overall strategy.

  • GSMT is a versatile observatory that will push back today’s limits in imaging and spectroscopy to open up new possibilities for the most important scientific problems identified in the Astro2010 survey. This exceptionally broad and powerful

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

ability over the whole range of astrophysical frontiers is the compelling argument for building GSMT.

  • Given the development schedules for GSMT, and in order to ensure the best science return for the U.S. public investment, it is both vital and urgent that NSF identify one U.S. project for continued support to prepare for its entry into the MREFC process.

Based on these conclusions, the panel recommends the following ordered priorities for the implementation of the major initiatives that form part of the research program in optical and infrared astronomy from the ground for the 2010-2020 decade:

  1. Given the panel’s top ranking of the Giant Segmented Mirror Telescope based on its scientific merit, the panel recommends that the National Science Foundation establish a process to select which one of the two U.S.-led GSMT concepts it will continue to support in preparation for entering the GSMT as soon as practicable into the MREFC line. This selection process should be completed within 1 year from the release of this panel report.

  2. The panel recommends that NSF and DOE commit as soon as possible but no later than 1 year from the release of this report, to supporting the construction of the Large Synoptic Survey Telescope. Because it will be several years before either GSMT project could reach the stage in the MREFC process that LSST occupies today, the panel recommends that LSST should precede GSMT into the MREFC approval process. The LSST construction should start no later than 2014 in order to maintain the project’s momentum, capture existing expertise, and provide critical synergy with GSMT.

  3. The panel recommends that NSF, following completion of the necessary reviews, should commit to supporting the construction of its selected GSMT through the MREFC line at an equivalent of a 25 percent share of the total construction cost, thereby securing a significant public partnership role in one of the GSMT projects.

  4. The panel recommends that in the longer term NSF should pursue the ultimate goal of a 50 percent public interest in GSMT capability, as articulated in the 2001 decadal survey (Astronomy and Astrophysics in the New Millennium). Reaching this goal will require (most likely in the decade 2021-2030) supporting one or both of the U.S.-led GSMT projects at a cost equivalent to an additional 25 percent GSMT interest for the federal government. The panel does not prescribe whether NSF’s long-term investment should be made through shared operations costs or through instrument development. Neither does the panel prescribe whether the additional investment should be made in the selected MREFC-supported GSMT in which a 25 percent partnership role is proposed already for the federal government.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

But the panel does recommend that, in the long run, additional support should be provided with the goal of attaining telescope access for the U.S. community corresponding to total public access to 50 percent of the equivalent of a GSMT.

Medium Projects and Activities

In assembling its prioritized program, the panel became convinced of the strategic importance of the entire national OIR enterprise, including all facilities—public and private. The panel crafted its program to maximize the scientific return for the entire U.S. astronomical community and to maintain a leading role for OIR astronomy on the global stage.

  • The panel recommends as its highest-priority medium activity a new medium-scale instrumentation program in NSF’s Division of Astronomical Sciences (AST) that supports projects with costs between those of standard grant funding and those for the MREFC line. To foster a balanced set of resources for the astronomical community, this program should be open to proposals to build (1) instruments for existing telescopes and (2) new telescopes across all ground-based astronomical activities, including solar astronomy and radio astronomy. The program should be designed and executed within the context of, and to maximize the achievement of science priorities of, the ground-based OIR system. Proposals to the medium-scale instrumentation program should be peer reviewed. OIR examples of activities that could be proposed for the program include massively multiplexed optical/near-IR spectrographs, adaptive optics systems for existing telescopes, and solar initiatives following on from the Advanced Technology Solar Telescope. The panel recommends funding this program at a level of approximately $20 million annually.

  • As its second-highest-priority medium activity, the panel recommends enhancing the support of the OIR system of telescopes by (1) increasing the funds for the Telescope System Instrumentation Program (TSIP) and (2) adding support for the small-aperture telescopes into a combined effort that will advance the capabilities and science priorities of the U.S. ground-based OIR system. The OIR system includes telescopes with apertures of all sizes, whereas the TSIP was established to address the needs of large telescopes. The panel recommends an increase in the TSIP budget to approximately $8 million (FY2009) annually. Additional funding for small-aperture telescopes in support of the recommendations of the National Optical Astronomy Observatory (NOAO) Renewing Small Telescopes for Astronomical Research (ReSTAR) committee (approximately $3 million per year) should augment the combined effort to a total of approximately $11 million (FY2009) to encompass all apertures. The combined effort will serve as a mechanism for co-ordinating the development of the OIR system. To be effective, the funding level

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

and funding opportunities for this effort must be consistent from year to year. Although it is possible that the total combined resources could be administered as a single program, the implementation of such a program raises difficult issues, such as formulas for the value of resources or the need to rebuild infrastructure. The panel considers the administration of two separate programs under the umbrella of “system development” to be a simpler alternative. The expanded TSIP and the mid-scale instrumentation program both provide opportunities to direct these instrumentation funds strategically toward optimizing and balancing the U.S. telescope system.

  • The U.S. system of OIR telescopes currently functions as a collection of federal and nonfederal telescope resources that would benefit from collaborative planning and management—for example, to avoid unnecessary instrument duplication between telescopes. The panel recommends that NSF ensure that such a mechanism exists, operating in close concert with the nonfederal observatories, for the management of the U.S. telescope system. The panel recommends that a high priority be given to renewing the system of ground-based OIR facilities, requiring a new strategic plan and a broadly accepted process for its implementation.

Small Programs

The panel concluded that initiating a tactical set of small targeted programs (each between $1 million and $3 million per year) would greatly benefit groundbased OIR science in the coming decade and would provide critical support for some of the medium and large programs. The panel recommends the small programs in the following, unprioritized list:

  • An adaptive optics technology-development program at the $2 million to $3 million per year level;

  • An interferometry operations and development program at a level of approximately $3 million per year;

  • An integrated ground-based-astronomy data-archiving program starting at a level of approximately $2 million per year and ramping down to approximately $1 million per year; and

  • A “strategic theory” program at the level of approximately $3 million per year.

Recommendations for Adjustments to Continuing Activities

The panel makes the following recommendations for continuing activities:

  • NSF should continue to support the National Solar Observatory (NSO) over the 2010-2020 decade to ensure that the Advanced Technology Solar Telescope

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

(ATST) becomes fully operational. ATST operations will require a ramp-up in NSO support to supplement savings that accrue from the planned closing of current solar facilities.

  • Funding for NOAO facilities should continue at approximately the FY2010 level.

  • The governance of the international Gemini Observatory should be restructured, in collaboration with all partners, to improve the responsiveness and accountability of the observatory to the goals and concerns of all its national user communities. As part of the restructuring negotiations, the United States should attempt to secure an additional fraction of the Gemini Observatory, including a proportional increase in the U.S. leadership role. The funding allocated for any augmentation in the U.S. share should be at most 10 percent of FY2010 U.S. Gemini spending. The United States should also seek improvements to the efficiency of Gemini operations. Efficiencies from streamlining Gemini operations, possibly achieved through a reforming of the national observatory to include NOAO and Gemini under a single operations team, should be applied to compensate for the loss of the United Kingdom from the Gemini partnership, thereby increasing the U.S. share. The United States should support the development of medium-scale, general-purpose Gemini instrumentation and upgrades at a steady level of about 10 percent of the U.S. share of operations costs. U.S. support for new large Gemini instruments (greater than approximately $20 million) should be competed against proposals for other instruments in the recommended mid-scale instrumentation program—a program aimed at meeting the needs of the overall U.S. OIR system discussed elsewhere in this panel report.

  • The NSF-AST grants program (Astronomy and Astrophysics Research Grants [AAG]) should be increased above the rate of inflation by approximately $40 million over the decade to enable the community to utilize the scientific capabilities of the new projects and enhanced OIR system.

  • NSF-AST should work closely with the NSF Office of Polar Programs to explore the potential for exploiting the unique characteristics of promising Antarctic sites.

The above program and the funding recommendations, presented in additional detail in the following sections of the panel’s report, represent a balanced program for U.S. OIR astronomy that is consistent with historical federal funding of astronomy and, more importantly, is poised to enable astronomers to answer the compelling science questions of the decade, as well as to open new windows of discovery. The proposed program involves an increased emphasis on partnerships, including NSF, DOE, NASA, U.S. federal institutions, state and private organizations, and international or foreign institutions. These partnerships not only are required by the scale of the new projects, which are beyond the capacity of any one institution or even one nation to undertake, but also are motivated by the

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

key capabilities that each of the partners brings to ensuring a dynamic scientific program throughout the decade.

The revolution in human understanding that began with Galileo’s telescope 400 years ago has not slowed down or lost its momentum—in fact it is accelerating—and the panel believes that it has identified the most promising areas for future investment by the United States in optical and infrared astronomy from the ground.

INTRODUCTION AND CONTEXT

Ground-based optical and infrared astronomy provides a fundamental basis for our knowledge of the universe at almost all astronomical scales. Moreover, OIR observations and facilities render astronomy accessible and inspirational to the general public. In the last decade, the development of new technologies has expanded our capabilities in many ways. In the time domain we are embarking on multi-epoch sky surveys, while in terms of spatial resolution ground-based telescopes are obtaining diffraction-limited images that surpass the angular resolution of current space telescopes.

The previous (2001) decadal survey, Astronomy and Astrophysics in the New Millennium (AANM), recommended two large activities and two medium activities for OIR: a giant (30-m-class) segmented-mirror, adaptive-optics-equipped, ground-based optical-infrared telescope, now known simply as the Giant Segmented Mirror Telescope (GSMT), and a large-aperture (6.5-m-class), very-wide-field (~3-deg) synoptic survey telescope to achieve an unprecedented combination of sky coverage, faint limiting magnitude, and time-domain coverage. The medium activities were an Advanced Technology Solar Telescope (ATST, called AST in AANM), support for developing the concept of treating the federally supported and independent observatories in the United States as a system, and using the system concept to increase the instrumentation capabilities and community access to U.S. OIR telescopes through a program called the Telescope System Instrumentation Program.

Progress has been made on all four initiatives. ATST has just entered its MREFC-funded construction phase. TSIP has operated at a low but significant level for almost the entire decade. Projects have been formed and developed as candidates for GSMT and the large-aperture, very-wide-field synoptic survey telescope.

The new observational capabilities introduced in the last decade fostered an exciting period of scientific discovery for OIR, fundamentally changing the way the contents and history of the universe are understood and capturing the imagination and interest of the general public. Notable examples include

  • Exoplanets. The discovery of a diverse set of extrasolar planets has defied many preconceived notions of the properties of other solar systems. Planet hunt-

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

ing is now pursued with an increasingly rich variety of survey techniques (each of which can probe different kinds of systems), including increasingly sensitive radial velocities, transit timing, microlensing, and adaptive optics imaging (Figure 7.1).

  • Dark energy and structure formation. The discovery of the acceleration of the expansion rate of the universe has profoundly altered our view of fundamental physics. Rapidly improving measurements of the acceleration, along with a detailed view of the large-scale structure of the universe, have established the lambda cold dark matter (ΛCDM) model as the standard model of cosmology.

  • Galactic-center black hole. Definitive proof for the existence of a supermassive black hole and the first detailed kinematic look at the way black holes interact with their stellar environments have been obtained through measurements of individual stellar orbits at the galactic center (Figure 7.2)

  • Gamma-ray bursts. The study of optical-IR afterglows of gamma-ray bursts (GRBs) has provided detailed light curves and redshifts of these events. This in turn has generated an understanding of their connection with supernovae and the birth of black holes, extending as far back as z = 8.2.

  • Milky Way satellite and streams. The discovery of new components, remnants, and companions to the Milky Way has significantly altered our picture of halo formation, the early stages of galaxy formation, and the importance of mergers (Figure 7.3).

  • Quasars and GRBs at first light. Quasars, powered by early supermassive black holes, have been discovered back to redshifts of 6. Observations of a z = 8.2 GRB have opened a new window for studying the deaths of massive stars when the universe was only 4 percent of its current age. The first detection of the effect of hydrogen absorption on quasar light from z = 6.4 now provides the signature of the last phases of the reionization of the universe (Figure 7.4).

  • Galaxies and massive black holes across cosmic time. The discovery and characterization of a tight (and unexpected) correlation between the mass of a supermassive black hole and the velocity dispersion of the host galaxy’s bulge has driven new ideas about the evolution of these objects. Determinations of the histories of cosmic star formation, chemical enrichment, and massive black hole accretion have provided additional input, supplemented by the discovery of a bimodal color-magnitude distribution in the galaxy population at the present epoch.

  • Brown dwarfs. Sky surveys have revealed hundreds of field brown dwarfs, objects that have a direct connection to the more difficult study of giant planets. This large sample has enabled the application of theoretical atmospheric models yielding a thorough understanding of their structure and composition, direct measurements of dynamical masses, and definitive elimination of brown dwarfs as dark matter candidates.

  • Kuiper belt objects. The discovery of objects within the solar system that are comparable to, or more massive than, Pluto has revolutionized our understanding of the constituents of the solar system.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.1 Top left: Exoplanet discoveries by year, color coded by discovery technique: radial velocity (blue), transit (green), timing (dark purple), astrometry (dark yellow), direct imaging (red), microlensing (orange), and pulsar timing (light purple). Top right: The first directly imaged multiple planet system (HR 8799; adaptive optics imaging in 2008). Bottom: Planetary system discovered by microlensing. SOURCE: Top left: Available at http://commons.wikimedia.org/wiki/File:Exoplanet_Discovery_ Methods_Bar.png#filehistory (19:35; October 3, 2010). Top right: National Research Council of Canada—Herzberg Institute of Astrophysics, C. Marois and Keck Observatory. Bottom: B.S. Gaudi, D.P. Bennett, A. Udalski, A. Gould, G.W. Christie, D. Maoz, S. Dong, J. McCormick, M.K. Szymaski, P.J. Tristram, S. Nikolaev, et al., Discovery of a Jupiter/Saturn analog with gravitational microlensing, Science 319(5865):927-930, 2008, reprinted with permission of AAAS.

FIGURE 7.1 Top left: Exoplanet discoveries by year, color coded by discovery technique: radial velocity (blue), transit (green), timing (dark purple), astrometry (dark yellow), direct imaging (red), microlensing (orange), and pulsar timing (light purple). Top right: The first directly imaged multiple planet system (HR 8799; adaptive optics imaging in 2008). Bottom: Planetary system discovered by microlensing. SOURCE: Top left: Available at http://commons.wikimedia.org/wiki/File:Exoplanet_Discovery_ Methods_Bar.png#filehistory (19:35; October 3, 2010). Top right: National Research Council of Canada—Herzberg Institute of Astrophysics, C. Marois and Keck Observatory. Bottom: B.S. Gaudi, D.P. Bennett, A. Udalski, A. Gould, G.W. Christie, D. Maoz, S. Dong, J. McCormick, M.K. Szymaski, P.J. Tristram, S. Nikolaev, et al., Discovery of a Jupiter/Saturn analog with gravitational microlensing, Science 319(5865):927-930, 2008, reprinted with permission of AAAS.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.2 Stellar orbits at the galactic center that have demonstrated the existence of a supermassive black hole and revealed the kinematic structure of surrounding stellar population, which is key to understanding the growth of black holes. SOURCE: Image courtesy of and created by Andrea Ghez and her research team at UCLA from data sets obtained with the W.M. Keck Telescopes.

FIGURE 7.2 Stellar orbits at the galactic center that have demonstrated the existence of a supermassive black hole and revealed the kinematic structure of surrounding stellar population, which is key to understanding the growth of black holes. SOURCE: Image courtesy of and created by Andrea Ghez and her research team at UCLA from data sets obtained with the W.M. Keck Telescopes.

FIGURE 7.3 Discovery of Milky Way streams. SOURCE: V. Belokurov and the Sloan Digital Sky Survey.

FIGURE 7.3 Discovery of Milky Way streams. SOURCE: V. Belokurov and the Sloan Digital Sky Survey.

  • Inside the Sun. Helioseismology revealed unanticipated temperature and velocity structures just beneath sunspots, measured interior flows that constrain solar-dynamo action throughout the convection zone, and made routine the detection of active regions on the far side of the Sun.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.4 Stack of quasar spectra showing Gunn-Peterson absorption trough. SOURCE: X. Fan, C.L. Carilli, and B. Keating, Observational constraints on cosmic reionization, Annual Review of Astronomy and Astrophysics 44:415-62, 2006.

FIGURE 7.4 Stack of quasar spectra showing Gunn-Peterson absorption trough. SOURCE: X. Fan, C.L. Carilli, and B. Keating, Observational constraints on cosmic reionization, Annual Review of Astronomy and Astrophysics 44:415-62, 2006.

  • A complex stellar atmosphere. An incessant flurry of mixed-polarity magnetic elements appears everywhere on the solar surface and above, down to the smallest resolvable scales. Energetic features and flows now observable in this transitional regime are being matched by increasingly realistic models of turbulent magneto-convection near the photosphere and in the exceedingly heterogeneous atmosphere (Figure 7.5).

These scientific achievements and many others have been enabled by the development of astronomical technologies. Two that stand out as particularly important are (1) the evolution of adaptive optics systems into scientifically ver-

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.5 This high-resolution solar image from the 1.6-m New Solar Telescope (NST) at Big Bear Solar Observatory demonstrates the advantage of a large aperture. Even without adaptive optics, this 4″ x 2″ speckle-reconstructed image from March 30, 2009, reveals seven side-by-side bright points in a dark lane at the center. Bright points are probably associated with magnetic field concentrations and are each about 0.1″ (75 km) in diameter. The beads cannot be seen in the image on the right that was degraded to the resolution of the old 0.6-m telescope. ATST, scheduled for first light in 2017, will have a 4-m aperture. SOURCE: Big Bear Solar Observatory/New Jersey Institute of Technology.

FIGURE 7.5 This high-resolution solar image from the 1.6-m New Solar Telescope (NST) at Big Bear Solar Observatory demonstrates the advantage of a large aperture. Even without adaptive optics, this 4″ x 2″ speckle-reconstructed image from March 30, 2009, reveals seven side-by-side bright points in a dark lane at the center. Bright points are probably associated with magnetic field concentrations and are each about 0.1″ (75 km) in diameter. The beads cannot be seen in the image on the right that was degraded to the resolution of the old 0.6-m telescope. ATST, scheduled for first light in 2017, will have a 4-m aperture. SOURCE: Big Bear Solar Observatory/New Jersey Institute of Technology.

satile and reliable user instrumentation and (2) the development of the hardware and software infrastructure to produce, distribute, and analyze large and reliable astronomical surveys.

The development of adaptive optics (AO) into a workhorse technology on most large ground-based telescopes (e.g, the Keck, VLT, Gemini, MMT, the Hale telescope, and the Dunn solar telescopes) has enabled diffraction-limited, near-IR imaging and spectroscopy previously possible only from space. Key technology developments include the production of stable lasers capable of generating a bright artificial guide star (Figure 7.6), large-format deformable mirrors, lower-noise wavefront sensors that allow fainter tip-tilt stars and natural guide stars to be detected, and the engineering of these components into reliable, optimized, and rugged systems that meet scientific needs. For example, the laser-guide-star AO system on the 10-m W.M. Keck II telescope routinely achieves an angular resolution of 0.04 arcsecond (with Strehl ratio >0.4 at 2.2 microns) in its laser-guide-star mode and can achieve this performance over a large fraction of the sky. In 2009, more than 150 refereed scientific papers were published based on AO data, 29 using laser-guide-star systems. Other critical developments important for both current and future AO systems include adaptive secondaries and three-dimensional tomographic analysis of atmospheric turbulence. Areas of scientific research benefiting from AO systems now range from studies within our own solar system (including

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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FIGURE 7.6 Three laser adaptive optics systems operating on Mauna Kea. SOURCE: © Subaru Telescope, National Astronomical Observatory of Japan. All rights reserved. Reprinted with permission.

FIGURE 7.6 Three laser adaptive optics systems operating on Mauna Kea. SOURCE: © Subaru Telescope, National Astronomical Observatory of Japan. All rights reserved. Reprinted with permission.

the Sun itself) to the most distant galaxies and include a number of truly transformative research results over the last decade (e.g., see Figures 7.1 and 7.2). The pace of technological development and scientific utilization of AO systems has occurred quite rapidly since the 2001 decadal survey, and astronomers now have powerful systems as part of the basic facility infrastructure on many telescopes. New, more specialized and powerful systems will soon be operational, including dedicated planet-finding, high-contrast imagers, wide-field multi-conjugate AO systems, and the powerful facility designed for the ATST.

Survey astronomy also has undergone a transformation in the past decade, with a profound impact not only on the science, but also on the culture of astronomy. Large, well-reduced, statistically rigorous data sets are now standard tools in most topics of OIR astronomy. These data sets are enabled by powerful instruments and a renewed commitment to data pipelines and archives. A key aspect of survey astronomy is that many science interests can be served simultaneously, including serendipitous discoveries and unanticipated opportunities. Surveys have the greatest impact when the full reduced data are made public, greatly increasing the com-

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.7 Imaging at milliarcsecond resolution is now becoming routine with today’s infrared interferometers. This recent image of Alderamin (α Cep) from the CHARA Array reveals the centrifugally distorted photosphere of this rapidly rotating star, strong “gravity darkening” along the equator, and hot emission at the poles. SOURCE: M. Zhao, J.D. Monnier, E. Pedretti, N. Thureau, A. Mérand, T. Ten Brummelaar, H. McAlister, S.T. Ridgway, N. Turner, J. Sturmann, L. Sturmann, P.J. Goldfinger, and C. Farrington, Imaging and modeling rapidly rotating stars: α Cephei and α Ophiuchi, Astrophysical Journal 701:209, 2009, reproduced by permission of the AAS.

FIGURE 7.7 Imaging at milliarcsecond resolution is now becoming routine with today’s infrared interferometers. This recent image of Alderamin (α Cep) from the CHARA Array reveals the centrifugally distorted photosphere of this rapidly rotating star, strong “gravity darkening” along the equator, and hot emission at the poles. SOURCE: M. Zhao, J.D. Monnier, E. Pedretti, N. Thureau, A. Mérand, T. Ten Brummelaar, H. McAlister, S.T. Ridgway, N. Turner, J. Sturmann, L. Sturmann, P.J. Goldfinger, and C. Farrington, Imaging and modeling rapidly rotating stars: α Cephei and α Ophiuchi, Astrophysical Journal 701:209, 2009, reproduced by permission of the AAS.

munity of people who can use the data. An increasing number of astronomers rely on data archives for their work, and new tools and protocols have been developed to serve, search, and cross-link these data sets and to find complex trends in the results.

Besides these two areas of major development, advances in many other technologies have provided significant improvement in the capabilities of ground-based OIR telescopes. These technologies include new generations of large-format optical and IR detector arrays; interferometry, with pairs of large telescopes and arrays of smaller ones (Figure 7.7); new, durable, low-emissivity mirror coatings; volume-phase holographic gratings; and AO-fed coronagraphs.

The structure of the astronomical enterprise has served the pursuit of ground-breaking science well. It will need to evolve further in the decades to come in order to make the most efficient use of, and provide the broadest access to, observational capabilities and thereby continue to advance the frontiers of our knowledge and answer the urgent science questions identified in this Astro2010 decadal survey of astronomy and astrophysics.

OPPORTUNITIES IN OIR SCIENCE

The Astro2010 Science Frontiers Panels have identified key research questions and discovery areas for the next decade. Ground-based OIR astronomy laid the foundations in many of these areas and is poised to enable transformative studies

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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to address these questions over the next decade (Table 7.1). Larger telescopes—with greater light grasp, AO-enabled resolution, and multiplex instruments—will tackle high-contrast investigations of objects ranging from the Sun to faint sources in crowded fields in nearby galaxies and at cosmological distances. Large-scale, high-sensitivity imaging surveys at high cadence will open the way for a thorough exploration of time-domain astronomy. New facilities, coupled with upgraded existing public and private resources, will enable astronomers to seek answers to some of the key scientific questions of our era—from the nature of dark matter and dark energy to the formation and evolution of galaxies, stars, and planets.

Determining the properties of exoplanetary systems and their disk progenitors remains a prime science objective of ground-based OIR astronomy (PSF 3 and PSF 5,2 Table 7.1; see Figure 7.8). The first insights are being gained into the structure of exoplanet systems with increased observational statistics and improved radial-velocity precision. Systematic campaigns with new high-precision radialvelocity spectrometers, particularly at near-IR wavelengths, can extend coverage to longer-period and lower-mass planets around later-type stars, approaching the level needed to detect Earth-like planets under the best conditions. Besides radialvelocity surveys, detection techniques now include transit surveys, gravitational microlensing surveys and direct imaging. Deepening the census of planets is a crucial step toward understanding formation processes. Transit techniques that combine discovery from the ground with space-based characterization and direct imaging and spectroscopy with advanced AO coronagraphs will let us measure the temperature and composition of the planets found. These new abilities have just begun to be exploited, and our knowledge of the physical properties of exoplanets will explode in the coming decade. Realizing progress over the next decade will require dedicated planet-detecting instruments (from IR Doppler spectrographs to high-contrast AO coronagraphs) on telescopes of all sizes from 2-m to GSMT-scale facilities. Ultimately, ground-based characterization and synoptic studies, complemented by space-based observations, will help us understand how solar systems form and whether systems like our own—including Earth-like planets—are common or rare.

High-contrast imaging and spectroscopy on 8-m and GSMT-class telescopes will map the structure and evolution of protoplanetary disks (PSF 2, Table 7.1) at angular separations exceeding 0.15 to 0.04 arcsecond, respectively, and contrast ratios from 10−7 to 10−9. GSMT-class telescopes offer the potential of detecting Jupiter analogs around nearby solar-type stars, and will directly complement ALMA submillimeter surveys investigating the kinematics and dust in protoplanetary

2

The questions and discovery areas developed by the five SFPs are identified throughout this report by the three-letter panel acronym plus question number and the letter “D” (for discovery area) as given in Table 7.1.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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TABLE 7.1 Contributions by OIR Facilities and Activities to Addressing Key Science Questions Identified by the Astro2010 Decadal Survey Science Frontiers Panels

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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aThe GAN SFP also identified time-domain astronomy as a discovery area for the next decade.

NOTE: The gray-intensity coding depicts the level of contribution(s) made by GSMTs, LSST, currently existing (public/private) OIR telescope facilities, mid-scale instrumentation, and current interferometry capabilities to addressing the science questions and discovery (D) areas identified by the five Astro2010 Science Frontiers Panels: Black indicates strong contributions to an SFP question or discovery area, dark gray indicates an important contribution, light gray indicates a minor contribution, and no coloring indicates no or no significant contribution. In the Mid-Scale Instrumentation column, it is noted where the contribution will come from: ExAO, future coronagraphic high-contrast, adaptive optics systems, including GSMT-class instrumentation; AO, future high-Strehl/visible-light laser-guide-star adaptive optics systems on 5- to 10-m telescopes; DWFIR, Deep, Wide-Field IR Survey; HPRV, high-precision radial-velocity spectroscopy; MOS, wide-field multiobject spectroscopy; and Solar, new solar instrumentation.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.8 Keck K-band image of the protoplanetary disk around the nearby young M dwarf, AU Mic. New-generation adaptive optics systems on 8- to 10-meter-class telescopes and GSMT will extend such observations to older, more distant systems. SOURCE: M. Liu, IfA-Hawaii/W.M. Keck Observatory.

FIGURE 7.8 Keck K-band image of the protoplanetary disk around the nearby young M dwarf, AU Mic. New-generation adaptive optics systems on 8- to 10-meter-class telescopes and GSMT will extend such observations to older, more distant systems. SOURCE: M. Liu, IfA-Hawaii/W.M. Keck Observatory.

disks. Thermal mid-IR observations trace warm dust in young systems, while high-resolution spectroscopy at blue and IR wavelengths probes gas kinematics at sub-AU (astronomical unit) resolution. Optical and near-IR measurements of scattered light map colder material and remnant debris disks. AO-assisted coronagraphy and polarimetry will be powerful tools for probing disks around young stars in the solar neighborhood, deriving dust composition, radial density, and size distributions. These observations will be complemented by synoptic surveys that will provide the first census of the size-frequency and compositional distributions of trans-neptunian objects in the outermost regions of our own solar system, reaching magnitude r ~ 24.5 and trans-neptunian objects with diameters as small as 25 km.

New OIR ground-based capabilities will also open new windows on one of the most critical astrophysical processes: the formation of stars (PSF 1, Table 7.1).

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

Detailed observations of star clusters spanning a range of ages, coupled with wide-angle surveys of nearby field stars, have resulted in broad consensus as to the overall form of the stellar initial mass function (IMF). Three key areas of uncertainty remain: at high masses (>10 solar masses) there are indications of variations in either the shape of the IMF or the upper-mass cutoff; at the opposite extreme it remains unclear whether there is a well-defined low-mass cutoff; finally, uncertainties remain concerning binary frequency and the role played by binary systems at all masses. Tackling these issues demands high-sensitivity, high-resolution imaging. AO-equipped 8-m telescopes can detect jovian-mass brown dwarfs in the nearest star-forming regions and can resolve binaries at separations exceeding 30 mas. GSMT-class telescopes can resolve high-mass stars in a wide range of star clusters in the nearby Andromeda galaxy and in star-forming regions in the nearer irregular galaxies, setting constraints on variations in the upper IMF within a range of environments.

Stellar-evolution theory represents a triumph of 20th century astrophysics. Recent technological developments and observational innovations put us in a position to refine and test that theory in unprecedented detail over the next decade. In particular, scientists will quantify the influence of magnetic fields, mass loss, and rotation through high-resolution, high-sensitivity spectroscopy and spectropolarimetry of individual stars (SSE 1, Table 7.1), as well as through direct imaging via long-baseline OIR interferometry.

The Sun is a key target, providing scope both for continuous, comprehensive measurements of global temporal changes (SSE D, Table 7.1) and for detailed observations of physical processes operating at the finest spatial and temporal scales, where plasma and magnetic fields interact. The 4-m ATST will reveal the Sun’s magnetic field at sub-arcsecond resolution and probe the complex transition region between the photosphere and the corona. Solar observations are key for three topics of broad astrophysical interest: (1) the origin and evolution of large- and small-scale magnetic flux elements; (2) the formation of chromospheres and coronae and the physics of energy transport in inhomogeneous, non-equilibrium atmospheres; and (3) energy storage and release in the dynamic corona, which lead to a range of events including flares, coronal mass ejections, and particle acceleration. Activity in the third has a significant impact on our understanding of Earth-Sun interactions, including space weather.

Within the galaxy, detailed surface-magnetic-field geometries can be reconstructed for active stars using (Zeeman) spectropolarimetry and Doppler tomography on high-throughput echelle spectrographs on large-aperture telescopes. The surfaces of nearby stars can be directly imaged using long-baseline infrared interferometry, probing photospheric distortions caused by rapid rotation or binary interactions. In the wider field, repeated full-sky monitoring by synoptic surveys promises a complete statistical view of stellar cycles and rare stellar events, includ-

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

ing flares that can tell us about magnetic-field properties for stars and brown dwarfs spanning the full range of masses. Maturing asteroseismology will provide insight into stars’ internal structure and dynamics.

Supernovae and gamma-ray bursts are two examples of stellar behavior whose characterization has implications that extend well beyond evolutionary theory (PSF 1; SSE 2, 3, and D; GAN 1, 2; see Figure 7.9). In neither case is there a good understanding of the progenitor population or of the full range of evolutionary pathways. Insight into both will be gained from studying the dramatic mass-loss and strong binary interactions seen in massive stars in the Milky Way, its satellites, and nearby galaxies, coupling AO-based spectroscopic and photometric analyses with interferometric data. Large-scale synoptic surveys will identify numerous supernovae and GRB afterglows, and detailed follow-up observations of well-chosen subsets will pinpoint their precise locations, providing either direct identification of the progenitor or insights gained through investigating the properties of its immediate stellar neighbors. Similar resources can also be deployed to identify and study the nature of sources of gravitational waves (CFP D). Investigations at different cosmic epochs will be supplemented by “galactic archeology,” using today’s abundance patterns of metal-poor stars—identified from multiobject spectroscopic follow-up of wide-field imaging surveys—to probe supernova frequencies and the enrichment history of the early Milky Way.

On larger scales, basic questions center on feedback mechanisms and energy transport in the interstellar medium and the recycling of circumgalactic gas in galaxies (GAN 1, 2; GCT 2). At high redshifts, OIR observations in the rest-frame ultraviolet detect winds from Lyman-break galaxies and directly measure the resulting spread of metals; in the lower-redshift universe, interstellar optical and near-ultraviolet lines also allow the tracking of galactic winds as a function of galaxy properties.

The star formation histories of galaxies, the growth of central black holes, the properties of dark matter halos, and the way interactions between those quantities are reflected in present-day galactic morphology are all crucial areas for research in the next decade (GAN 3, 4, and D; GCT 1, 3). In recent years, precision measurements across cosmic time have led to a widely accepted cosmological paradigm for galaxy assembly and evolution, the ΛCDM model (see Figure 7.10). Within this theory, galaxies form “bottom-up,” with low-mass objects (“halos”) collapsing earlier and merging to form larger and larger systems over time. Ordinary matter follows the dynamics dictated by the dominant dark matter until radiative, hydrodynamic, and star-formation processes take over (GCT 2). Although ΛCDM has had great success in explaining the observed large-scale distribution of mass in the universe, the nature of the dark matter particle is best tested on small scales, where its interaction properties manifest themselves by modifying the structure of galaxy halos and their clumpiness (CFP 4). On these scales, detailed comparisons

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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FIGURE 7.9 A menagerie of supernovae from the SDSS survey. The LSST program will identify tens of thousands of such objects. SOURCE: Ben Dilday and the Sloan Digital Sky Survey (SDSS) Collaboration.

FIGURE 7.9 A menagerie of supernovae from the SDSS survey. The LSST program will identify tens of thousands of such objects. SOURCE: Ben Dilday and the Sloan Digital Sky Survey (SDSS) Collaboration.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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FIGURE 7.10 Simulations of the ΛCDM cosmic web. SOURCE: A. Jenkins, C.S. Frenk, F.R. Pearce, P.A. Thomas, J.M. Colberg, S.D.M. White, H.M.P. Couchman, J.A. Peacock, G. Efstathiou, and A.H. Nelson, Evolution of structure in cold dark matter universes, Astrophysical Journal 499:20-40, 1998. Courtesy of Joerg Colberg and the Virgo Consortium.

FIGURE 7.10 Simulations of the ΛCDM cosmic web. SOURCE: A. Jenkins, C.S. Frenk, F.R. Pearce, P.A. Thomas, J.M. Colberg, S.D.M. White, H.M.P. Couchman, J.A. Peacock, G. Efstathiou, and A.H. Nelson, Evolution of structure in cold dark matter universes, Astrophysical Journal 499:20-40, 1998. Courtesy of Joerg Colberg and the Virgo Consortium.

between observation and theory reveal several discrepancies, such as the apparent mismatch between the galaxy’s relatively smooth stellar halo and the extremely clumpy dark matter distribution predicted by numerical simulations (the “missing satellite problem”). Ground-based OIR observations will discover fainter and more distant satellites and streams, confirming their existence, measuring velocity dispersions and dark matter properties, and dramatically constraining the formation of structure in ΛCDM.

Optical and near-infrared color-magnitude diagrams remain a highly effective means of probing the star formation history in nearby galaxies, and the next generation of telescopes will extend observations to more crowded environments and greater distances (PSF 1, GAN 2). Those investigations complement the early

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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star-formation history inferred from galactic archaeology (GAN 3), and a GSMT-class telescope offers the potential of resolving horizontal-branch stars in the nearest ellipticals. High-angular-resolution imaging and spectroscopy can focus on galactic cores (including the galactic center); measure stellar and gaseous motions to 1-kms1 accuracy, more than an order of magnitude better than current measurements; and probe the detailed structure of the stellar cusps and the mass of nuclear black holes. At the same time, spectroscopic and astrometric measurements (with 30-μas accuracy) of stars in the Milky Way’s outer halo and its satellites can measure space motions at accuracies better than 5 kms−1 and map the distribution of dark matter on larger scales (GAN 4, 5).

Large-scale spectroscopic surveys using multiobject instruments on 4- to 10-meter-class telescopes will be vital in probing the growth of structure at low and intermediate redshifts and tracing the demographics of black holes and active galaxies (GCT 1, 3). Follow-up observations on a GSMT-class telescope can use emission lines to investigate the chemical enrichment of distant galaxies at the peak of their star formation activity (redshift z ~ 2-4). The light-gathering power of a GSMT at low-background, near-IR wavelengths is such that its AO-assisted spectroscopic performance at moderate resolution (R = 100-1,000) is 10 to 100 times better than JWST. AO-fed integral-field-unit spectrographs will reveal the internal structures, kinematics, and metallicities of those systems. Absorption-line studies using background probes will enable a detailed understanding of the topology, ionization state, and chemical enrichment of the intergalactic medium (GCT 2).

The first dwarf-size galaxies will contain massive stars formed from primordial gas (Population III): these subgalactic stellar systems, aided perhaps by a population of accreting black holes in their nuclei, generated the UV radiation that reheated and reionized the universe at the end of the cosmic dark ages (GCT 4, 5). Although JWST has a clear advantage in near-IR imaging of high-redshift sources, once identified, near-IR spectroscopy on an AO-assisted GSMT-class telescope is significantly more efficient and will provide a more detailed story of the properties and influence of the first stars on the intergalactic medium.

OIR will remain in the forefront in our quest for the mapping of cosmological initial conditions over the widest possible dynamic range (CFP 1, 2, 4), through observations of large-scale structure (using galaxies, intergalactic gas, and gravitational lensing) and of standard candles (primarily Type Ia supernovae). While supernovae and baryonic acoustic oscillations provide complementary methods for measuring the distance-redshift relation, weak lensing is sensitive both to distances and to the growth of dark matter clustering. Improved distance measurements can test whether the distance-redshift relationship follows the form expected for vacuum energy or whether the dark energy evolves with time. Measurements of the growth rate of large-scale structure provide an independent probe of the effects of dark energy. The combination of distance and growth constraints tests the

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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validity of general relativity on large scales. These goals can be reached by future, large, ground-based optical-imaging surveys that will provide high-signal-to-noise (S/N > 20), multiband, optical data for >109 galaxies to I = 25, permitting measurements of shape and photo-z for galaxies at redshifts z < 2, angular-correlation measurements to z ~ 4, and detections to z ~ 5. Additionally, ground-based optical facilities with highly multiplexed, wide-field spectrographs can survey several million galaxies at z > 1, and use baryonic acoustic oscillations to constrain H(z). Standard candles will remain crucial for cosmological investigations at lower redshifts, where large-scale-structure methods are limited by cosmic variance (GCT 1). Future synoptic imaging surveys will identify tens of thousands of well-measured Type Ia supernovae, accumulating millions of observations by the end of the decade. Spectroscopic follow-up on 8-m and, for a very limited subset, GSMT-class telescopes will be crucial for characterizing the subclasses of those objects and testing for systematic deviations from the norm.

In summary, ground-based OIR observations remain essential in key science areas ranging from exoplanet research to dark energy and from solar physics to large-scale cosmology. The new facilities and programs outlined in the following section will be integral to successful progress in the next decade.

FUTURE PROGRAMS IN OIR ASTRONOMY

This section describes the projects and activities that the OIR Panel (henceforth the panel) is recommending for support, including those of large, medium, and small scope, as well as continuing activities and U.S. participation in the Gemini Observatory. The large and medium activities are presented in this section in priority order within their respective categories. The section “Recommended Priorities and Plan for the Next Decade” brings the large, medium, small, and continuing activities together, presenting a prioritized implementation plan that describes a balanced program in U.S. ground-based OIR astronomy that fits within the budgetary guidelines given to the panel.

Large Programs

The 200-inch telescope on Mt. Palomar was constructed over a period of more than 20 years. It dominated ground-based astronomy for two decades from 1950 and continued as a leading instrument until the next generation of giant telescopes was constructed in the 1990s. Like the 200-inch, the large programs described here are at the forefront of engineering and technical imagination and will be central to astrophysics for decades to come. Whether the topic is circumstellar disks, exploding stars, the fossil record of galaxy assembly, black holes, or cosmic acceleration, present knowledge shows that there are tantalizing and decisive observations that

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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lie just beyond the grasp of today’s telescopes. To answer the questions highlighted by the Science Frontiers Panels (see Table 7.1), America’s astronomers need to build the telescopes of tomorrow. The panel is convinced that the community knows how to build the instruments needed to answer these pressing science questions. The panel urges a prompt start on these great enterprises.

The Giant Segmented Mirror Telescope (GSMT)

The GSMT projects currently under development in the United States are 25-to 30-m-class telescopes for optical and near-IR observations with instruments that will open new frontiers of research across the entire optical and near-IR spectral regions observable from the ground.

GSMT is a versatile observatory that will push back today’s limits in imaging and spectroscopy to open up new possibilities for the most important scientific problems identified by the Science Frontiers Panels. This exceptionally broad and powerful ability over the whole range of astrophysical frontiers is the compelling argument for building GSMT. To make this explicit, in Table 7.1 the panel indicates the ways in which the GSMTs being designed today will address 18 of the 20 science questions and 4 of the 5 discovery areas that the SFPs have identified as today’s most important scientific frontiers. These span the range from exoplanets around nearby stars to galaxies beyond redshift 7, where new abilities afforded by GSMT to image at its diffraction limit and to obtain extremely deep multiobject spectra will lead to decisive advances in our field. While it is no coincidence that these telescope designs address the most important scientific problems understood today, a GSMT also has the potential to adapt to new technology and to new scientific questions in the future. As with the other great ground-based observatories, an ongoing program of instrument development will ensure that the telescopes built in the coming decade will have capabilities that remain at the technological forefront and can be focused on the most pressing scientific questions of the coming decades.

The great strength of a GSMT lies in the breadth of its capabilities and the breathtaking new regions of angular resolution, sensitivity, and speed that it will open up for the first time. Two U.S.-led projects for a GSMT, the Giant Magellan Telescope and the Thirty Meter Telescope are technologically ready. They collect 5 to 9 times as much light as the most powerful telescopes operating today. With the capable AO systems planned for early operation, these telescopes will make images that are 3 times sharper than those obtained with existing ground-based telescopes (and 10 times sharper than HST’s!) In many situations where this type of imaging is useful, the exposure time it takes to make an image of a given quality scales as 1/D4, where D is the telescope diameter. This means that the gain in speed over the largest existing telescopes is an astonishing factor of 70. Five nights on GSMT

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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would be worth a year on today’s telescopes, opening up new possibilities for ambitious work and making the study of fast-changing events possible for the first time.

GSMT will open up discovery space in remarkable new directions. They will probe dense environments within the Milky Way and in nearby galaxies and, coupled with advanced AO, map planetary systems around nearby stars. Achieving an astrometric precision better than 30 to 50 micro-arcseconds, GSMT capabilities will approach those of planned space missions while offering sensitivities that are, in some cases, almost 10 magnitudes better. With rapid-response capabilities coupled to sensitive, high-resolution spectroscopy, GSMTs will be vital to characterizing the physical properties, and the environments, of new variable sources discovered in synoptic surveys, including flare stars, novae, supernovae, GRBs, and, eventually, gravitational-wave sources. GSMT sensitivity will be crucial in detailed investigations of discoveries from existing and planned facilities—including JWST, ALMA, and LSST—in science areas ranging from probing star and planet formation in the solar neighborhood to understanding the properties of the first stars and the reionization era. Table 7.2 provides five specific examples of key science programs that are made possible only by GSMTs.

Given the range of crucial and unique capabilities that are integral to addressing so many high-priority questions, the panel concluded that GSMTs must be pursued vigorously in the coming decade.

TABLE 7.2 Five of the Key Science Programs That Can Be Addressed Only with a GSMT

SFP Question

Science

Capability

Synergies

PSF 2, 3

Direct detection and spectroscopy of giant exoplanets; orbital measurement and characterization of disk environments

High-sensitivity adaptive optics (AO)-assisted coronagraphy and IFU spectroscopy

JWST, ALMA

GAN D, GCT 3

Orbital characteristics of faint sources near the galactic center; measuring the black hole mass and R0 to 1 percent and testing GR in the medium-field regime

High-sensitivity, high-precision AO-assisted astrometry in crowded fields

 

SSE 2, D; CFP 2

Spectroscopy and imaging of supernovae and GRBs and their environments; characterizing the progenitors of Type Ia supernovae and testing

High-sensitivity, high-precision AO-assisted photometry and spectroscopy in crowded fields

LSST, JWST

GAN 4, GCT 1

Radial-velocity and proper-motion measurements for hundreds of stars in dwarf galaxies; probing velocity anisotrop, and the nature and form of the underlying dark matter

High-sensitivity, high-precision AO-assisted astrometry and spectroscopy in crowded fields

 

GCT 4, 5

Near-infrared spectroscopy of galaxies and large, forming star clusters that are gravitationally lensed or that are rich in massive stars at redshifts z > 7; probing the physical properties of the first stars

High-sensitivity, high-precision spectroscopy at the faintest magnitudes

JWST, ALMA

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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The U.S. GSMT Projects As mentioned above, there are two U.S. GSMT projects: the Giant Magellan Telescope and the Thirty Meter Telescope. They are described next, in alphabetical order.


The Giant Magellan Telescope (GMT) The GMT project design makes use of seven 8.4-m-diameter mirrors to achieve an overall primary mirror with the resolving power of a 24.5-m diameter mirror (Figure 7.11). The baseline project includes the telescope, an adaptive secondary mirror system, and an initial suite of three to four instruments to be selected in 2011 from eight concepts currently under development (Figure 7.12). An international partnership has been formed to construct and operate GMT. It consists of the Carnegie Institution for Science, Harvard University, the Smithsonian Astrophysical Observatory, Texas A&M University, the University of Texas at Austin, and the University of Arizona from the United States; the Korea Astronomy and Space Science Institute, representing Korea; and the Australian National University, together with Astronomy Australia, Ltd., on behalf of Australian astronomers.

The GMT project office and staff have been established in Pasadena, and the project completed its conceptual design phase in 2006, following a successful conceptual design review. More than 30 people from across the partnership are actively involved in the project. The project-management team has developed a full work breakdown structure and schedule and produced a total cost appraisal for the project. The project is now in the design development phase, which is scheduled to end in 2011 with a system preliminary design review and submission of the implementation plan for construction and commissioning. The project recognized early on that production of the primary mirror segments is on the critical path and acted in 2005 to cast the first 8.4-m primary mirror segment in the Steward Observatory Mirror Laboratory (SOML). Since then SOML has been working on figuring and polishing the mirror segment, and the overall fabrication effort is 85 percent complete. The site for the telescope has been selected. It will be located at the Las Campanas Observatory in Chile, which already has six operating telescopes, including the two Magellan 6.5-m telescopes.

FIGURE 7.11 The current GMT observatory design shown as it would appear on Cerro Las Campanas. SOURCE: Courtesy of GMTO; image by Todd Mason/Mason Productions.

FIGURE 7.11 The current GMT observatory design shown as it would appear on Cerro Las Campanas. SOURCE: Courtesy of GMTO; image by Todd Mason/Mason Productions.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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FIGURE 7.12 Examples of simulations of gains to be realized from the GSMT’s aperture and adaptive optics. Upper: Simulated H-band images of a globular cluster at the distance of NGC5128 (Cen A) with a 3-pc core radius. The left panel shows a simulated image with the resolution of HST; the center panel corresponds to an 8-m aperture, and the right image uses the GMT PSF and 4-mas pixels. Each panel is 2″ on a side. Lower: Color-magnitude diagrams for M32. Gemini observations (left) are compared to simulated data for JWST (center) and GSMT with adaptive optics (right). The power of the large aperture in resolving crowded regions is clearly demonstrated in this simulation. SOURCE: Upper: P. McCarthy et al., “Giant Magellan Telescope Project: Response to the DS2010 Activity RFI,” Astro2010 white paper, available by request from the National Academies Public Access Records Office at http://www8.nationalacademies.org/cp/ManageRequest.aspx?key=48964. Lower: K. Olsen et al., “The Star Formation Histories of Disk and E/S0 Galaxies from Resolved Stars,” Astro2010 white paper, available at http://sites.nationalacademies.org/BPA/BPA_050603, last accessed February 2011.

FIGURE 7.12 Examples of simulations of gains to be realized from the GSMT’s aperture and adaptive optics. Upper: Simulated H-band images of a globular cluster at the distance of NGC5128 (Cen A) with a 3-pc core radius. The left panel shows a simulated image with the resolution of HST; the center panel corresponds to an 8-m aperture, and the right image uses the GMT PSF and 4-mas pixels. Each panel is 2″ on a side. Lower: Color-magnitude diagrams for M32. Gemini observations (left) are compared to simulated data for JWST (center) and GSMT with adaptive optics (right). The power of the large aperture in resolving crowded regions is clearly demonstrated in this simulation. SOURCE: Upper: P. McCarthy et al., “Giant Magellan Telescope Project: Response to the DS2010 Activity RFI,” Astro2010 white paper, available by request from the National Academies Public Access Records Office at http://www8.nationalacademies.org/cp/ManageRequest.aspx?key=48964. Lower: K. Olsen et al., “The Star Formation Histories of Disk and E/S0 Galaxies from Resolved Stars,” Astro2010 white paper, available at http://sites.nationalacademies.org/BPA/BPA_050603, last accessed February 2011.

The GMT project estimates the cost to complete the project—including corporate and project office and systems engineering, telescope system and optics, adaptive optics, instrumentation, enclosure and facilities—to be $686 million (FY2009 dollars), a value that includes an overall 20 percent reserve. The operations budget, including continuing facility and instrumentation development, is estimated to be $36 million per year in FY2009 dollars. The current schedule calls for early science

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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operations beginning in 2018, with the project phase ending near the end of the decade, 1 year later.


The Thirty Meter Telescope (TMT) The TMT project plans to build a 30-m primary mirror consisting of 492 segments, each 1.45 m in size (Figure 7.13). The telescope, located at the Hawaiian Mauna Kea Observatory, will have an AO system and an initial suite of three instruments, including an infrared-imaging spectrograph, an infrared multi-slit spectrograph, and a wide-field optical spectrograph (Figure 7.14). An international partnership comprising a group of Canadian universities, Caltech, and the University of California has been formed to carry out the project. The National Observatory of Japan is a collaborating institution in the project, and China has recently joined the effort as an observer. The TMT Project Office and staff have been established, and in March 2009 the project successfully completed its 5-year, $77 million design development phase. It subsequently entered its early construction phase with the goal of beginning construction in 2011.

Approximately 40 full-time technical personnel are engaged in TMT design and early construction studies at the Project Office in Pasadena, with a nearly equal number distributed at the various partner institutions. The technical level of TMT is enhanced by a work breakdown structure that is five to seven levels deep for the majority of the project, a complete and well-staffed systems-engineering approach, and organized and “well-positioned” software development. In collaboration with the European ELT project, which has substantially similar mirror segments, four polishers are currently engaged in studies of large-scale segment production. Extensive science flowdown has been established to the engineering requirements for the project, and a detailed science case has been in place since 2007. A draft state

FIGURE 7.13 The current TMT observatory design. SOURCE: TMT Observatory Corporation.

FIGURE 7.13 The current TMT observatory design. SOURCE: TMT Observatory Corporation.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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FIGURE 7.14 Imaging of the galactic center with a speckle interferometer, the Keck Observatory with its current adaptive optics system, and the simulated performance of TMT with adaptive optics, showing individual stars orbiting the supermassive black hole. The TMT observations detect enough stars with sufficient precision that their orbital paths can be used to test the predictions of general relativity. SOURCE: Image courtesy of and created by Andrea Ghez and her research team at UCLA from data sets obtained with the W.M. Keck Telescopes.

FIGURE 7.14 Imaging of the galactic center with a speckle interferometer, the Keck Observatory with its current adaptive optics system, and the simulated performance of TMT with adaptive optics, showing individual stars orbiting the supermassive black hole. The TMT observations detect enough stars with sufficient precision that their orbital paths can be used to test the predictions of general relativity. SOURCE: Image courtesy of and created by Andrea Ghez and her research team at UCLA from data sets obtained with the W.M. Keck Telescopes.

environmental impact study for the chosen Hawaiian site was published in May 2009, and a final study is expected in early 2010.

The TMT project estimates that the cost to complete the project—including facilities telescope, AO and instruments, operations design and observatory software, and project management and system engineering—is $987 million (FY2009 dollars), a value that includes a 30 percent contingency. Operating costs are estimated to be $54 million per year, including $20 million per year for new instrumentation. The project goal is to achieve first light in 2018.


Assessment of Technical Readiness, Cost, and Schedule for GSMT The panel had available to it two reviews of the U.S. GSMT projects. First, a non-advocate community assessment of the status of both GMT and TMT (GCAR) was carried out in 2009 by the National Optical Astronomy Observatory (NOAO) as GSMT program manager for NSF. A main goal of the review was to determine the progress of both projects toward the NSF-mandated preliminary design review needed for a major facility. Second, as part of the Astro2010 survey process, an independent analysis of GMT and TMT was carried out by Aerospace Corporation, a consulting firm hired by the National Research Council as part of the survey’s assessment of technical readiness and schedule/cost risks. This independent assessment was called the cost appraisal and technical evaluation (CATE). The CATE process did not evaluate operating costs.

Having assessed these two sources of independent information on the GSMT projects, the OIR Panel found that the technology needed to build a GSMT exists. In summary, the panel found as follows.

The GMT builds on the successful heritage of the 6.5-m Magellan Telescopes and the twin 8.4-m Large Binocular Telescope (LBT). The TMT builds on the

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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successful design of the 10-m Keck Telescopes with their segmented mirrors, a technology that the European Extremely Large Telescope has also selected.

Adaptive optics is a key area for both projects, since the justification for building a large (20- to 30-m) telescope hinges on achieving diffraction-limited images to enable revolutionary science. AO for GSMT-scale telescopes is practical given current technology. Deformable mirrors, wavefront sensors, tomographic reconstruction algorithms, and lasers all exist in prototype forms that will be straightforward to scale to the requirements for a GSMT. The TMT project has completed a preliminary design for its first-light AO system, NFIRAOS, which could be constructed today using existing technologies. GMT plans to use deformable mirrors that are very similar in size and complexity to the adaptive secondary mirrors now being completed for the LBT. Although AO for a GSMT is an order of magnitude more challenging than the first AO systems on 5- to 10-m telescopes, a new generation of instruments bridges the gap. Specialized high-performance facilities—extreme AO designed for planet-imaging, multi-laser wide-field AO, or prototype visible-light AO systems—are being deployed on 5- to 10-m telescopes in the next 1 to 5 years. To achieve extreme performance on an 8- to 10-m telescope requires technology close to that required for general-purpose AO on 20- to 30-m telescopes. Table 7.3 compares the requirements of NFIRAOS to AO systems commissioned at the beginning of the last decade and to the state of the art at the beginning of this decade. Other AO modes (e.g., high-contrast ExAO) require

TABLE 7.3 Comparison of Adaptive Optics (AO) Component Specifications for Three Systems

Component

Keck AO LGS (2003)a

Current State of the Art (2011)b

TMT NFIRAOS (2018)c

N = Diameter of deformable mirror (DM) in actuators and actuator spacing

N = 16 actuators at 1-cm spacing

N = 41 actuators at 0.5-cm spacing

N = 64 actuators at 0.25-cm and 0.04-cm spacing N = 64 and N = 76 actuators at 0.5-cm spacing

Visible-light wavefront sensor (WFS) detector

64 × 64 pixels at 700 Hz, 8 e noise

160 × 160 pixels at 1500 Hz, 3 e noise

360 × 360 pixels at 800 Hz, 3 e noise

Lasers

1 × 15 W

1 × 50 W

6 × 25 W

Wavefront control algorithm

Least-squares reconstruction between single DM and single WFS

Least-squares reconstruction between 5 WFSs and 3 DMs

Maximum-likelihood tomography between 6 WFSs and 2 DMs

Wavefront reconstruction computational scale, rate, and hardware

480 × 349 at 700 Hz (high-performance CPUs)

6,000 × 3,000 at 2,000 Hz (multiple GPUs)

35,000 × 7,000 at 800 Hz (field-programmable gate array architecture)

aFirst-generation Keck laser-guide-star system.

bNext-generation systems being commissioned on 5- to 8-m telescopes in 2011 (Palomar PALM3000, Gemini Multiconjugate AO and Gemini Planet Imager, and VLT SPHERE instruments).

cRequirements for AO for a GSMT.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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further technology development that would be supported by an AO development program (see below). The panel believes that there is a clear path for scaling to the requisite level and extensive opportunities for testing before final implementation on a completed GSMT.

The independent CATE assessment found that the technical risk of GMT, independent of cost, is medium. For the GMT, key technical and project challenges noted in the two external assessments include:

  1. Production and metrology of primary mirror segments; the six off-axis 8.4-m segments are a particular challenge;

  2. Alignment and phasing of primary mirror segments;

  3. Design and production of segments for an adaptive secondary mirror;

  4. Other AO components, particularly lasers;

  5. Insufficient instrument maturity and cost allocation; and

  6. The need to strengthen project management and system engineering.

The independent CATE assessment is that cost and schedule risk for the GMT is medium-high in comparison to the project’s estimates. Based on the available information, the CATE assessment concluded that a full cost appraisal is not possible at this time. Therefore a cost sensitivity analysis was carried out for the primary mirrors and instruments. That analysis yielded a cost appraisal (at a 70 percent confidence level) that was roughly 60 percent higher than the cost appraisal provided by GMT project personnel, which would take the cost without operations from $689 million to $1.1 billion. The cost risks for the primary mirrors are increased polishing and metrology costs above current estimates and the cost growth associated with a 24-month schedule delay. The result for the growth in instrument costs is based on experience with 20 space projects at a similar level of development and the assumption that the cost growth would be similar.

The CATE assessment rated the schedule risk to be 4 years, with primary mirror fabrication and completion of the AO system and science instruments being the main risk items. Note that the independent assessment used the completion of all initial instrumentation and the AO system as defining the end of the project.

For the TMT, the community assessment review places the TMT project at a preliminary design review level essentially consistent with the initial readiness reviews necessary for NSF major facilities consideration. The CATE independent assessment noted the following key challenges:

  1. Meeting the very ambitious production plan for primary optics—492 segments for the primary mirror, 82 spare segments, and 82 different optical prescriptions;

  2. Segment alignment and phasing;

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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  1. AO components, particularly lasers; and

  2. Insufficient instrument maturity and cost allocation.

A key finding of the independent CATE assessment for TMT was that the typical reduction in manufacturing time for each doubling of a mass-production line, as proposed for the primary mirror segments, is likely only 20 percent. Applying this to the production rate demonstrated for Keck segments yields 152 months as opposed to 82 months to produce the 574 segments if only a single production facility is used. Use of a second vendor or production line would reduce this to 104 months. The overall technical risk for TMT, independent of cost, is judged to be medium high.

The CATE assessment of the cost and schedule risk for TMT is judged to be high in comparison to the project’s estimates. A cost-sensitivity analysis for the primary mirrors and instruments developed by the independent contractor yielded a cost appraisal (at a 70 percent confidence level) about 42 percent higher than the cost appraisal provided by the TMT project personnel, which would increase the cost from $987 million to about $1.4 billion. The main factors in the cost risk for the primary mirrors are the uncertainties in the ability of external vendors to meet the cost and schedule estimates of the project. As with GMT, the result for the growth in instrument costs is based on experience with space projects at a similar level of development and the assumption that the cost growth would be similar. The independent estimate of the schedule risk is 3 to 6 years, depending on the approach used to fabricate the primary mirror segments.

Based on the outcomes of the independent assessments, the panel concluded that both U.S.-led GSMT projects should in the near term undergo an independent full cost and schedule review as they proceed through any NSF down-select, preliminary design review, or major facility review process.


The Community and Federal Participation in GSMT Because of the vast array of key science questions GSMTs address and the large, broad, and diverse U.S. community that will use the telescopes, the panel concludes that the United States should ideally amass a total share of 50 percent of the equivalent of a GSMT, made up from one or both of the GSMT projects, consistent with the recommendation of AANM, the 2001 decadal survey.

It is expected that U.S. community access to a GSMT project would be awarded in a competitive process and would be commensurate with the share in construction and operations costs provided by the federal government. Maximizing community access would also require participation in the decision-making process for future development of the telescope (especially instrumentation), as discussed elsewhere in this panel report.

The panel finds that national participation in a GSMT must be well integrated

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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into the U.S. system. As a result, the panel concludes that the only tenable outcome is national participation in at least one GSMT as a full, decision-making (>25 percent) partner that is able to guide instrument choices and operational considerations. Given the GSMT development schedules, the panel believes that it is both vital and urgent that NSF identify one U.S. project to join as a partner at this level.

The European Southern Observatory (ESO) has announced plans to build a 42-m GSMT, the European Extremely Large Telescope (E-ELT), as its highest priority. E-ELT design work has been progressing rapidly, and the U.S. community must consider its role in light of these concrete plans. The panel does not recommend joining the E-ELT project, in part because the panel recognizes the importance of leveraging the private and nonfederal contributions to TMT and GMT for the benefit of U.S. astronomy, which will likely total well over $1 billion. At the initial proposed contribution level of a 25 percent share in a GSMT, the role the United States would play in the E-ELT would be too small to secure a scientific and technical leadership position for the nation in the project. Further, if the United States joined the E-ELT project it would simultaneously compete with the GMT and TMT projects, which would undercut U.S. aspirations to be a leader in ground-based astronomy. In addition, as a minor partner in the E-ELT, which is tied to the European system of telescopes, integration with the U.S. system would not be possible.

For the past century, U.S. astronomers have enjoyed access to the most powerful telescopes in the world, and this technological edge has led to transformative discoveries and a vibrant community. Maintaining this momentum is vital to the health of science in this country, as serious international challenges are faced. The panel concluded that without community involvement in a GSMT project, U.S. astronomy is in danger of becoming uncompetitive in the next, and succeeding, decades.

The Large Synoptic Survey Telescope (LSST)

“Wide-fast-deep” are the key words for LSST, a project that developed from a high-priority recommendation of the 2001 AANM: “a large-aperture (6.5-m-class), very-wide-field (~3 deg) synoptic survey telescope” (p. 107). The project has four main science goals: to explore the nature of dark energy, study the solar system, investigate optical transients, and study galactic structure. LSST will perform systematic, repeated surveys of the entire available sky to depths of 24th magnitude at optical wavelengths. Combining repeated survey images will provide composite wide-field images extending more than 10-fold fainter. LSST synoptic data will revolutionize investigations of transient phenomena, directly addressing the key discovery area of time-domain astronomy highlighted by two of the Astro2010 SFPs. LSST data will be invaluable in surveys of regular and irregular variable sources, both galactic and extragalactic, and in astrometry of objects in the solar system and the solar neighborhood (Table 7.4). At the same time, the combined

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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TABLE 7.4 Five of the Key Science Programs That Can Be Accomplished Only with LSST

SFP Question

Science Program

Capability

Synergies

PSF 2, GAN 5, SSE D

Composition and orbital structure of the outer solar system: 10- to 100-fold increased census of trans-neptunian objects and other small bodies to r ~ 24.5

High-sensitivity, high-cadence, multiband, wide-field synoptic imaging

JWST, ALMA, GSMT

SSE 2, D; CFP 2

Identifying and characterizing Type Ia supernovae to z ~ 0.5-0.7 and using those observations to constrain the dark-energy equation of state

High-sensitivity, high-cadence, multiband, synoptic, wide-field imaging

OIR System, GSMT

GAN 3

Architecture and formation history of the MW: identifying very metal-poor stars and mapping star streams in the galactic halo to ~100 kpc using main-sequence subdwarfs and RR Lyraes

High-sensitivity, high-cadence, multiband, wide-field imaging

OIR System, GSMT

GCT 1, CFP 1

Measurement of baryonic acoustic oscillations and cluster growth: large-scale structure from photometric redshifts for ~1010 galaxies

High-sensitivity, multiband imaging over ~20,000 square degrees to r ~ 27

 

CFP 1, 2

Constraints on dark energy from weak lensing measurements for ~3 billion galaxies

High-sensitivity, multiband imaging over ~20,000 square degrees to r ~ 27

 

images will provide a multiwaveband, homogeneous, wide-field-imaging data set of unparalleled sensitivity that can be used to address a wide range of high-impact scientific issues. All told, LSST will address 14 of the 20 questions raised by the SFPs and 4 of the 5 discovery areas (Table 7.1).

Substantial progress toward realizing the LSST vision has occurred during the past decade. The LSST project, a consortium of 30 universities and research institutions, plans to build a survey telescope with an 8.4-m primary mirror and a 6.7-m effective aperture on Cerro Pachon, Chile. Its 3.2-gigapixel camera, covering a 9.6-deg2 field of view, will give LSST an effective entendue of 319 m2 deg2, which will be more than 10 times greater than that of any other telescope (Figure 7.15). The telescope will survey the sky over a period of 10 years, during which time each field will be observed 1,000 times in six filter bands and produce 30 terabytes of data per night (Figure 7.16). The project has a credible plan for making the data and tools to analyze them available to the scientific community and the public.

The project is nearing the end of its design-development phase and expects to be ready for construction beginning in 2011. More than 100 technical personnel from across the partner institutions are currently involved in the project. The project uses state-of-the-art project-management techniques for design, system engineering, and cost and schedule planning. Highlights of achievements to date reported by the project include (1) preparation of preliminary engineering designs for major subsystems to estimate both performance and cost; (2) development of a detailed work breakdown structure for the project to the sixth level; (3) estimation

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.15 The 8.4-meter LSST will use a special three-mirror design creating an exceptionally wide field of view, and it will have the ability to survey the entire sky at any given time of year in a single filter in only three nights. SOURCE: LSST Corporation.

FIGURE 7.15 The 8.4-meter LSST will use a special three-mirror design creating an exceptionally wide field of view, and it will have the ability to survey the entire sky at any given time of year in a single filter in only three nights. SOURCE: LSST Corporation.

of costs based on a detailed work breakdown structure, estimates from potential manufacturers, and prior experience with similar projects; (4) completion of all prerequisites for Chilean governmental permission to construct the telescope, including environmental permitting; (5) placing contracts for casting and polishing the primary/tertiary mirrors; (6) casting the 8.4-m primary/tertiary mirror; (7) contracting for and casting the secondary mirror blank; (8) completion of the science requirements, and their flowdown to engineering/system requirements; (9) and producing the 600-page LSST Science Book,3 which demonstrates the level of community involvement and reflects the level of scientific promise.

The project estimates that the cost of LSST—including the project-management office, telescope and site, camera, data management, education and outreach, and commissioning—to be $455 million (2009 dollars). This value in-

3

LSST Science Collaborations and LSST Project 2009, LSST Science Book, Version 2.0, arXiv: 0912.0201, http://www.lsst.org/lsst/scibook.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.16 A simulated image of one 15-second exposure with the LSST charge-coupled device (4K × 4K) with 0.2″ pixels, 0.4″ seeing, and a field of view of 13.7′ × 13.7′, representing roughly 0.5 percent of the LSST focal plane. The brightest stars in the image are 12th magnitude. An object of brightness 33rd magnitude would record 1 photon in a 15-second exposure. The image is a true-color composite of three images, with the g, r, and i filters mapped into B, G, and R colors, respectively. Each color channel is on a logarithmic intensity scale. LSST will produce 2 billion single-band images of the same size. SOURCE: LSST Corporation © 2009. Reprinted with permission.

FIGURE 7.16 A simulated image of one 15-second exposure with the LSST charge-coupled device (4K × 4K) with 0.2″ pixels, 0.4″ seeing, and a field of view of 13.7′ × 13.7′, representing roughly 0.5 percent of the LSST focal plane. The brightest stars in the image are 12th magnitude. An object of brightness 33rd magnitude would record 1 photon in a 15-second exposure. The image is a true-color composite of three images, with the g, r, and i filters mapped into B, G, and R colors, respectively. Each color channel is on a logarithmic intensity scale. LSST will produce 2 billion single-band images of the same size. SOURCE: LSST Corporation © 2009. Reprinted with permission.

cludes a contingency of $101 million. Of the total, $299 million is to be requested from NSF, $84 million from DOE, and the balance from other and nonfederal resources. Operations costs are estimated to be $40.9 million per year, with NSF and DOE shares each being one-third, or $13.7 million per year. The remaining third will be sought from other sources.


Assessment of Technical Readiness, Cost, and Schedule for LSST The independent contractor rated the overall technical risk of the LSST project as medium low. The CATE process identified the main remaining risks and concerns as:

  1. Support structure for the secondary mirror and camera;

  2. Maturity of focal plane arrays for the camera and their procurement;

  3. Production of the large camera elements;

  4. Camera mechanisms;

  5. Data management challenges; and

  6. Achieving the mirror surface figure specifications.

The LSST team acknowledges these challenges and should be able to achieve the performance goals and commission the telescope system prior to 2020.

The independent assessment of the LSST project cost produced a value that was slightly below the project values, primarily in the areas of the telescope, optics, and software. However, the contractor was unable to assess the costs of instruments for the ground-based facilities because of a lack of analogous data, and so the costs associated with the camera were not assessed. Because the camera is both a technically challenging item and on the critical path for the LSST schedule, the panel finds it prudent to use the project’s cost appraisal pending the detailed cost review that will occur following the NSF preliminary design review. The independent

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

assessment of the LSST construction schedule yielded an increase of 15 months and a completion date of the end of 2018 relative to the project estimate, with the production schedule for the detectors and camera being the main risk item. No assessment was made of the $41 million annual operating cost appraisal.

The panel concluded that LSST is technologically ready and is the most advanced toward construction readiness of the three large projects under consideration by the panel.


Additional Comments and Conclusions for LSST The panel notes that follow-up observations are critical to many LSST science goals. Time-critical spectroscopy of variable and transient objects is the most important need. Photometric follow-up of variables, particularly those that brighten beyond the saturation limit of LSST, is also important. The U.S. system in its current form, even if augmented by a giant 30-m telescope, is likely insufficient to provide enough follow-up capability. Strong consideration should be given to strategic use of 4- and 8-m-class telescopes in direct support of the LSST project. The LSST project is understandably devoting its efforts to creating the LSST facility itself, but the panel concluded that additional attention to arranging the necessary follow-up observational capabilities to fully exploit LSST is essential.

LSST will result in significant changes in the modes of research carried out by much of the United States and, indeed, the global astronomical community. If properly supported, the archive will enable frontier research by scientists at institutions without their own telescope resources. LSST will foster large collaborative teams of researchers probing the broader science goals. This project has very significant computational challenges, in terms of data acquisition, processing, and storage, and data-mining algorithms. Solutions to these problems will require input from the information technology community and may well generate positive payback to society well beyond the astronomical research community.

The high value and transformative nature of LSST derives from the production of a high-quality public archive and the investment of effort by a wide spectrum of astronomical users. The panel believes that the LSST project has vigorously and effectively engaged this aspect of its mission and concludes that the project is well scoped and costed, with a detailed science-operations plan. Based on its own analysis of the information provided to it by the proponents of LSST and by the survey’s independent contractor, the panel concluded that the LSST project is in an advanced state and ready for immediate implementation.

GSMT and LSST as a Coordinated Program

Rather than view its prioritization as a competition between GSMT and LSST, the panel stresses the synergy of these two projects. Scientific coordination be-

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

tween GSMT and LSST will be robust regardless of the ultimate sites selected for the projects; even if the projects are located in opposite hemispheres there will be substantial overlap in the sky accessible to both. Further, each would be greatly enhanced by the existence of the other, and the omission of either would be a significant loss. The combination of wide-area photometric surveys and large-aperture spectroscopy has a long, productive history in OIR astronomy, grounded in the 1950s with the combination of the Palomar 48-inch Schmidt and the Hale 200-inch and supplemented in later years by the NOAO 4-m telescopes. Interesting sources identified in the wide-field survey are studied in detail with the larger telescope. An aperture ratio of ~5:1 is particularly useful: the area ratio of ~25 combined with an exposure-time ratio of up to 2 orders of magnitude appropriately couples the capabilities of broad-band photometry to low/medium-resolution spectroscopy. More recently, the combination of the Sloan Digital Sky Survey and new 8- to 10-m class telescopes provided a 4-fold increase in aperture, coupled with order-of-magnitude improvements in detector quantum efficiency.

Thus the combination of GSMT and LSST would create a particularly powerful opportunity for another series of breakthroughs. The power of this combination can be seen in Figure 7.17, which demonstrates the wide range of SFP questions to which both GSMT and LSST apply. The panel notes that these are not overlapping capabilities—rather they are in all cases complementary. LSST will provide photometry and time-series data for large numbers of objects, while GSMT will provide highly detailed studies of critical targets.

The panel concluded that a crucial goal for ground-based OIR astronomy in the coming decade should be to realize the potential of the combination of these facilities as linchpins for an upgraded comprehensive U.S. OIR system of telescopes.

Medium Programs
Mid-Scale Projects and Instrumentation

The OIR Panel’s highest priority for a medium-scale initiative is support for the NSF Mid-Scale Projects and Instrumentation program. Construction pathways are needed for powerful new specialized capabilities that will provide the sensitive measurements needed to answer the highest-priority science questions. Those capabilities include new instruments for existing and new telescopes, new mid-size facilities, large surveys, and technical-development programs. The cost of construction and operation of such capabilities falls in the ~$8 million to $120 million gap between the existing NSF Major Research Instrumentation (MRI) and MREFC programs; they are not easily funded in the current ground-based astronomical landscape. This Mid-Scale Projects and Instrumentation program is essential for the United States to effectively realize the full capabilities of the astronomical system.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
FIGURE 7.17 Venn diagram showing the interrelationship of GSMT and LSST for addressing the main science questions identified by the Astro2010 Science Frontiers Panels (see Table 7.1).

FIGURE 7.17 Venn diagram showing the interrelationship of GSMT and LSST for addressing the main science questions identified by the Astro2010 Science Frontiers Panels (see Table 7.1).

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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Cutting-edge astronomical instrumentation has significantly increased in cost over the past 20 years. As examples, the DEIMOS spectrograph for the Keck Observatory (completed in 2002) cost approximately $14 million in FY2009 dollars ($21 million with indirect costs), while the proposed Gemini WFMOS concept exceeded $65 million. There are several reasons for this:

  • Scale. Instruments for 8- to 10-m telescopes are necessarily larger and more sensitive than those for smaller telescopes.

  • Increased scientific capabilities. Most telescopes already are equipped with simple imagers and moderate-resolution spectrographs. Providing significant enhancements over current capabilities requires complex systems that employ new technologies, such as large-scale multiplexed spectrographs or advanced adaptive optics.

  • Data management and software complexity. As instrumental output increases from megabytes to gigabytes and terabytes, costs also increase, and this is all the more applicable to survey instruments where sophisticated pipelines are needed to provide fully reduced data products.

In addition, projects of this scale require appropriate management and contracting approaches to control cost and schedule and to reduce ultimate cost over-runs. This can increase initial, up-front costs and in some cases requires involvement of capable and more expensive non-university institutions such as national laboratories or aerospace companies.

Another factor is that some of the most important and exciting instrument proposals concentrate on a particular scientific question or must be optimized for a specific capability, rather than being general-purpose facilities. Again, this is in part due to progress during the previous decade—most observatories have complete suites of general-purpose instruments, and the questions within their reach are being answered; new scientific questions will often require very challenging observations necessitating instruments designed specifically to address those questions.

Several new OIR instruments or facilities proposed for the next decade that would provide revolutionary scientific capabilities include:

  • Massively multiplexed optical/near-IR spectrographs and spectroscopic surveys on 4- to 8-m telescopes to map large-scale structure for the study of dark energy and cosmology (CFP 1, 2, 3), to measure the evolution of galaxies across redshift and environment using spectral diagnostics (GCN 1), and to study the chemical and dynamical history of the Milky Way with large spectroscopic samples of stars (GCN 4, GAN 3, SSE 3). Several SFPs identified the need for surveys at least an order of magnitude larger than those currently underway; such surveys require new instrumentation for either fully or highly dedicated facilities, as well as large

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

survey teams. BigBOSS and HETDEX are compelling examples of next-generation projects in this category.

  • Next-generation AO systems, ranging from wider-field-of-view systems based on ground-layer and multi-conjugate AO to improved narrow-field systems, to provide diffraction-limited capability at visible-light wavelengths. Such systems will enable diffraction-limited spectroscopy of the cores of nearby galaxies to study the environments of massive black holes (GCT 3), integral-field spectroscopy to study the stellar constituents and kinematics of galaxies during the crucial epoch at z = 1.5-2.5 when most galaxies and stars are forming (GCT 1), and high-resolution studies of the multiplicity of solar system minor bodies to provide important information about the history of their formation, in addition to more familiar applications to the detection and characterization of planets and protoplanetary disks (PSF 2, 3) and stellar birth and death (PSF 1; SSE 2, 3)

  • New solar instruments and observatories to complement the unprecedented high-resolution view of ATST. A robust suite of more-capable, full-Sun, synoptic observations is needed to characterize the evolving global context, explore the solar interior, map the coronal magnetic field (SSE 1), and enable long-term timedomain studies (SSE D). Proposals for new facilities such as a coronal magnetism observatory that will provide measurements of the coronal magnetic field to understand structure, dynamics, and particle acceleration in a stellar atmosphere are examples of solar projects for the mid-scale program. Second-generation instrumentation for the ATST telescope is another important category.

Additional examples include:

  • Precision IR Doppler measurements to detect Earth-analog planets orbiting red dwarf stars and enhanced visible-light Doppler capabilities, perhaps with a dedicated 4-m telescope (PSF 3 and D).

  • Specialized scientific capabilities for the future GSMTs, such as ultrahigh-contrast planet imaging that could directly detect mature giant or “super-Earth” planets (PSF 3).

  • IR surveys leveraging the enormous advances in IR array technology to provide several-orders-of-magnitude increase in sensitivity over 2MASS and synoptic sky coverage (GCT 1 and D).

These projects are not well matched to existing NSF astronomical funding programs. They are too large for the Advanced Technologies and Instrumentation (ATI), MRI, and TSIP programs. Moreover, the mid-scale program is intended to (1) cover all ground-based astronomy, including solar and radio, millimeter, and submillimeter projects as well as OIR, (2) support proposals for new telescopes, and (3) allow for instrument upgrades to federally supported telescopes. TSIP, in

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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contrast, is for existing, large, nonfederal telescopes in the nighttime OIR system. In the past, projects in the range of the mid-scale program have been funded by NSF in response to unsolicited proposals, but this approach also creates problems, with no clearly defined process for principal investigators to follow, no easy way to select projects that match to particular scientific goals, and an opaque selection process.

The panel recommends supporting the Mid-Scale Projects and Instrumentation program at the level of $20 million per year to address the needs outlined above.

The approach would be analogous to the NASA Explorer missions, where projects are driven by the scientific vision of a team (rather than an imposed set of outside requirements), focused around a set of well-articulated high-priority science goals, cost-capped, but allowing for innovation. Typically this would fund instruments, telescopes, or projects with an NSF cost of $10 million to $30 million; some might exceed $50 million. The panel notes that in many of these cases, costs would be shared with other federal agencies or partners. In a steady state, the program might be funded at the level of $20 million per year, allowing it to support two to five projects at any given time, with projects initially funded only through a conceptual design for later down-select.

Selection criteria would include scientific merit, connections to research priorities set out in agency reports such as those of the AAAC Task Forces, project management, quality of the team, realism of the project plan, workforce development benefits, and the outcome of a conceptual design review. Public access to data products after an appropriate period (most likely through the archive centers recommended below in this report) would be expected unless explicitly restricted for scientific reasons. Public access to telescopes involved would depend on the nature of the project—this program is not intended to replace TSIP funding of general-purpose instruments for the broad community but instead to fund advanced facilities judged on their scientific merit.4

It is anticipated that this program would largely replace the current ad hoc funding of major unsolicited proposals. The panel notes that while it has focused on possible OIR concepts for such a program, it would encourage the program to include all wavelengths.

Strengthening the U.S. Telescope System in the Next Decade

The OIR Panel’s second-highest-priority, medium-scale initiative is enhancing funding to strengthen the U.S. telescope system in the next decade. The number of research telescopes of all apertures available to U.S. astronomers surpasses that of ESO and other countries, yet these facilities do not deliver their full combined

4

For example, the Sloan Digital Sky Survey provided public access to its data but not to the telescope and instruments, which were not designed for, or used in, a guest-observer mode.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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potential because technical effort is duplicated and not every facility has the resources to run at peak efficiency.

The 2001 decadal survey (AANM) advocated a “system” approach toward the entire suite of U.S. OIR facilities in order to encourage collaborations between federally funded and independent observatories so that federal funds are leveraged by private investment. AANM went on to recommend a Telescope System Instrumentation Program (TSIP) as its “highest-priority moderate initiative … [TSIP] would substantially increase NSF funding for instrumentation at large telescopes owned by independent observatories and provide new observing opportunities for the entire U.S. astronomical community” (pp. 12-13). AANM recommended a funding level of $50 million over the decade. A productive TSIP was established by NSF in 2002 and has since awarded $25 million, securing public observing time on nonfederal facilities with apertures >6 meters in return for new instrumentation (Figure 7.18). However, these investments have not strategically guided instrument choices or effectively coordinated activities across the portfolio of large telescopes.

Recently NOAO has engaged the community via two studies, ReSTAR and ALTAIR,5 that have assessed the science goals and U.S. telescope system performance for telescopes with apertures below and above 6 m, respectively. Combined, these reports suggest that a true system is manifold, including telescopes from 1-m aperture up to the 30-m-class GSMTs with telescopes at every level providing fundamental input toward answering the leading science questions of the next decade. Smaller telescopes are an integral component because they provide survey and time-domain support complementing large-telescope science, execute time-intensive programs unique to small apertures, provide the hands-on training ground for the next generation of observers and instrumentalists, and can serve as dedicated, single-instrument facilities, focused on specific scientific questions.

As the cost of instrumentation grows and as the GSMTs begin construction that will not be completed until the end of the decade, the opportunity remains ripe for federal investment in nonfederal facilities and for these investments to play a role in shaping a more efficient federal/nonfederal telescope system. Coordinating the unique power of the U.S. system, however, is a complex task. Strategies cannot be imposed centrally but must be implemented by generating incentives that foster community and efficiency across highly diverse groups and institutions. Investments have to be coordinated without expecting the individual components of the system to relinquish the leadership opportunities that they value, but should encourage independent observatories to consider the broader national perspective in framing their programs. Not surprisingly, the panel’s view of the next steps in

5

ReSTAR report, available at http://www.noao.edu/system/restar/files/ReSTAR_final_14jan08.pdf. Accessed May 2010. ALTAIR report, available at http://www.noao.edu/system/altair/. Accessed August 2010.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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FIGURE 7.18 The network of federal and nonfederal observatories, allied for excellence in scientific research, education, and public outreach, that enable experimentation and exploration throughout the observable universe. Telescopes pictured from top: First row: Gemini North with its laser-guide-star (LGS) system (courtesy of Gemini Observatory); Magellan Clay and Baade Telescopes (used with permission of the Observatories of the Carnegie Institution for Science); Lick Observatory Shane Telescope (courtesy of Lawrence Livermore National Laboratory); Large Binocular Telescope Observatory (courtesy of Large Binocular Telescope Corporation). Second row: Hobby-Eberly Telescope (courtesy of Thomas A. Sebring, West Texas Time Machine: Creating the Hobby-Eberly Telescope, Little Hands of Concrete Productions, 1998); Multiple Mirror Telescope (MMT) Observatory (courtesy of Howard Lester, MMTO); Keck Telescopes (courtesy of W.M. Keck Observatory). Third row: Small and Moderate Aperture Research Telescope System (SMARTS)/Cerro-Tololo International Observatory (courtesy of NOAO/AURA/NSF); Kitt Peak 4-meter Mayall telescope (courtesy of NOAO/AURA/NSF); Wisconsin-Indiana-Yale-NOAO (WIYN) Telescope (courtesy of Mark Hanna/NOAO/AURA/NSF); Palomar Observatory’s 200-inch Hale Telescope (courtesy of Scott Kardel/Caltech/Palomar Observatory). Fourth row: The Southern Astrophysical Research (SOAR) Telescope (© Southern Astrophysical Research Consortium, Inc.; all rights reserved; reprinted with permission); Ritter Observatory (courtesy of Erica N. Hesselbach); WIYN 0.9-meter Observatory (courtesy of NOAO/AURA/NSF); Astrophysical Research Consortium 3.5-meter Telescope (courtesy of Dan Long, Apache Point Observatory). Fifth row: Dunn Solar Telescope (courtesy of NSO/AURA Inc. and NSF); Wilcox Solar Observatory (courtesy of Wilcox Solar Observatory at Stanford University); Mt. Wilson Solar Observatory (© 2003 The Regents of the University of California; all rights reserved; reprinted with permission); Big Bear Solar Observatory (courtesy of Big Bear Solar Observatory/New Jersey Institute of Technology); McMath-Pierce/SOLIS solar telescope (courtesy of NOAO/AURA/NSF).

FIGURE 7.18 The network of federal and nonfederal observatories, allied for excellence in scientific research, education, and public outreach, that enable experimentation and exploration throughout the observable universe. Telescopes pictured from top: First row: Gemini North with its laser-guide-star (LGS) system (courtesy of Gemini Observatory); Magellan Clay and Baade Telescopes (used with permission of the Observatories of the Carnegie Institution for Science); Lick Observatory Shane Telescope (courtesy of Lawrence Livermore National Laboratory); Large Binocular Telescope Observatory (courtesy of Large Binocular Telescope Corporation). Second row: Hobby-Eberly Telescope (courtesy of Thomas A. Sebring, West Texas Time Machine: Creating the Hobby-Eberly Telescope, Little Hands of Concrete Productions, 1998); Multiple Mirror Telescope (MMT) Observatory (courtesy of Howard Lester, MMTO); Keck Telescopes (courtesy of W.M. Keck Observatory). Third row: Small and Moderate Aperture Research Telescope System (SMARTS)/Cerro-Tololo International Observatory (courtesy of NOAO/AURA/NSF); Kitt Peak 4-meter Mayall telescope (courtesy of NOAO/AURA/NSF); Wisconsin-Indiana-Yale-NOAO (WIYN) Telescope (courtesy of Mark Hanna/NOAO/AURA/NSF); Palomar Observatory’s 200-inch Hale Telescope (courtesy of Scott Kardel/Caltech/Palomar Observatory). Fourth row: The Southern Astrophysical Research (SOAR) Telescope (© Southern Astrophysical Research Consortium, Inc.; all rights reserved; reprinted with permission); Ritter Observatory (courtesy of Erica N. Hesselbach); WIYN 0.9-meter Observatory (courtesy of NOAO/AURA/NSF); Astrophysical Research Consortium 3.5-meter Telescope (courtesy of Dan Long, Apache Point Observatory). Fifth row: Dunn Solar Telescope (courtesy of NSO/AURA Inc. and NSF); Wilcox Solar Observatory (courtesy of Wilcox Solar Observatory at Stanford University); Mt. Wilson Solar Observatory (© 2003 The Regents of the University of California; all rights reserved; reprinted with permission); Big Bear Solar Observatory (courtesy of Big Bear Solar Observatory/New Jersey Institute of Technology); McMath-Pierce/SOLIS solar telescope (courtesy of NOAO/AURA/NSF).

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

the evolution of the system was varied. At the two extremes were a more ambitious version of the current approach to managing the system and a new, more-strategic approach. In detail, these extremes would entail:

  1. A more ambitious version of the status quo would include an augmented TSIP providing substantially increased support (both directly via current programs and also via the proposed expansion of “mid-scale” instrumentation). Support would also be extended to telescopes with smaller apertures. Awarding the increased support would be governed by the free market of peer review, and modest brokering by NSF/NOAO could provide guidance to balance these resources in the name of efficiency.

  2. An aggressively managed system would entail creating an entity (with suggestions ranging from an NOAO advisory panel to an openly competed “Telescope System Institute”) which—working with the same augmented TSIP/mid-scale resources—would be charged with providing active guidance to maximize the utility of the existing suite of telescopes, with the goal of avoiding duplication of expensive instrumentation. Another goal would be to broker federal and nonfederal time trades to relieve the pressure for instrument duplication.

By ceding a modest amount of autonomy, all players can ultimately exploit a system that interprets broad community needs and manages the available incentives to the greatest benefit while preserving the individual, entrepreneurial, and multi-component aspects of U.S. astronomy that have made it so successful in the past century. Doubling TSIP funding and introducing a mid-scale instrumentation program provides the resources needed to develop the incentives to realize these goals. An increase in the annual TSIP to $8 million would allow several instruments in the $5 million to $10 million cost range to be funded continuously. This range is typical of instruments funded by TSIP, such as the Keck instrument MOSFIRE and the WIYN One Degree Imager. The operators of the large nonfederal facilities have indicated that they would be willing to provide time to the community up to approximately this level. Given the strong community oversubscription for TSIP time on private facilities, often exceeding time on other national facilities, the panel believes that the community should obtain whatever time can be made available in this way. Furthermore, the large nonfederal facilities have indicated that this ongoing level would provide stability and predictability that would motivate them to seek longer-term commitments to partner with the federal side. This stability was not characteristic of the program in the past decade but is essential for building the system in the next. These incentives should also extend to embrace smaller telescopes, as outlined in the ReSTAR report.

As the era is approached in which the OIR system evolves to include the new initiatives—GSMT and LSST—at its apex, the panel believes that it is critical that

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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the supporting and complementary capabilities are maintained and improved. The panel expects that any future sales of shares of U.S.-led facilities will be made with consideration of the system so that opportunities to make those facilities available to the U.S. user community are always given consideration. At the same time, care must be taken to ensure that the TSIP/mid-scale programs provide adequate incentives for private observatories to actively partner with the national system rather than simply trading time for cash. Examples of incentives for partnering might include trading or sharing time on different instruments in the system and establishing partnerships to enable new projects

The panel recommends the following for the OIR system:

  • NSF-AST should reaffirm the national observatory’s role of leading and coordinating the development of the U.S. ground-based OIR system, with the understanding that all relevant groups will be involved in both planning and implementing its development.

  • The system should provide ongoing guidance toward fulfilling identified needs and seizing new scientific and technical opportunities.

  • The panel recommends enhancing the support of the OIR system of telescopes by (1) increasing the funds for the Telescope System Instrumentation Program (TSIP) and (2) adding support for the small-aperture telescopes into a combined effort that will advance the capabilities and science priorities of the U.S. ground-based OIR system. The OIR system includes telescopes with apertures of all sizes, whereas the TSIP was established to address the needs of large telescopes. The panel recommends an increase in the TSIP budget to ~$8 million (FY2009) annually. Additional funding for small-aperture telescopes in support of the recommendations of the NOAO ReSTAR committee (~$3 million per year) should augment the combined effort to a total of ~$11 million (FY2009) to encompass all apertures. The combined effort will serve as a mechanism for coordinating the development of the U.S. OIR system. To be effective, the funding level and funding opportunities for this effort must be consistent from year to year. Although it is possible that the total combined resources could be administered as a single program, the implementation of such a program raises difficult issues, such as formulas for the value of resources or the need to rebuild infrastructure. The panel considers the administration of two separate programs under the umbrella of system development to be a simpler alternative.

  • The expanded TSIP and the mid-scale instrumentation program both provide opportunities to direct these instrumentation funds strategically toward optimizing and balancing the U.S. telescope system. The system currently functions as a collection of federal and nonfederal telescope resources that would benefit from collaborative planning and management—for example to avoid unnecessary duplication of instruments between telescopes. The panel recommends that NSF

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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ensure that a mechanism exists, operating in close concert with the nonfederal observatories, for the management of the U.S. telescope system.

Small Programs

The OIR Panel identified the following smaller programs and activities as essential for maintaining a balanced program of U.S. astronomy and astrophysics and for providing the technological base and the support needed for the large and medium activities mentioned above. The panel did not prioritize these activities.

Optical Interferometry

OIR interferometry enables milli-arcsecond resolution and thus can reveal signs of planet formation around young stars, study rapid rotation and magnetic fields in nearby stars, image mass loss in massive and solar-mass stars, contribute to studies of supernova Type Ia progenitors, and deliver precision astrometry for exoplanet and galactic center studies—all in aid of addressing key SFP questions.

OIR interferometry is still a young and growing discipline, currently pursued by a handful of specialized groups. Support for interferometry in the coming decade should focus on advancing the technology while making interferometry more accessible to mainstream astronomers. Doing so sets the stage for the development of a facility-level interferometer a decade hence. The NSF University Radio Observatory program provides dedicated support to university radio observatories (UROs) in exchange for community access.

The panel recommends that NSF establish an equivalent program for OIR interferometry at a level of ~$3 million per year that would primarily fund competitive proposals for partial operations support of OIR interferometers in return for public access.

This program would also fund community resources supporting the development of new public users of these facilities. The program should also support technology development for interferometry in a manner analogous to the adaptive optics development program (AODP; discussed below). If funding for this program is not available, the TSIP should be broadened to include optical interferometers.

Adaptive Optics Development Program

As discussed above in the section “Introduction and Context” the near-IR adaptive optics systems are routinely used on the world’s largest telescopes, and as discussed in the section “Future Programs in OIR Astronomy,” the technological framework exists to extend this capability to a GSMT. AO at visible-light wavelengths, however, is currently feasible only on very bright targets and will require

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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significant development. AO currently has sufficient technological maturity to support first-light AO systems on GSMT. There are several areas of investment needed to move toward higher-performance AO on GSMT and existing telescopes, including development of lasers, innovative wavefront sensors and detectors, high-density deformable mirrors, and very large, adaptive secondary or curved tertiary mirrors. The AO community has prepared a technology development roadmap to reach these ambitious goals. A dedicated AO technology-development program is required for success. NSF briefly funded such a program in the past decade, but without a sustained investment, progress has almost halted; the existing NSF-AST grant programs are not well suited to strategic development of a particular technology.

The panel recommends an AO technology-development program at a level of $2 million to $3 million per year.

Next-Generation Technology

Technology development continues to drive observational progress in OIR astronomy. Beyond AO and interferometry programs, other evident technological needs—such as next-generation detectors, astro-photonics, lightweight mirrors, and fiber positioners—must be supported. These challenges can be met and prioritized through the peer-review process within the NSF ATI and MRI programs and NASA and DOE technology programs, assuming that these programs continue to receive the same fraction of the overall growing budgets. The panel endorses the current balance and mix of technology and instrumentation within NSF ATI/MRI, emphasizing that robust investment in technology development is essential to continued astronomical advances and future breakthrough instruments. The panel also notes that the Mid-Scale Projects and Instrumentation program could fund technology development in support of larger objectives that are beyond the scope of ATI. As important as the technology itself, appropriate support for the development and strengthening of the technology workforce should be part of technology efforts during the coming decade.

Archives and Archive Curation

Over the past decade, astronomy has become data-intensive. Open-access archives are commonplace for space missions and can double scientific productivity for a small fraction of the original mission cost. Archival research is a growing component of ground-based OIR astronomy, particularly for student and postdoctoral research. In Europe, ~15 percent of publications that use observations from the ESO include archival data. In the United States, archives have been established for large-scale surveys, notably the Sloan Digital Sky Survey (SDSS) and the 2-Micron

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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All-Sky Survey (2MASS); individual observatories (e.g., Keck, Gemini) are establishing archives for selected instruments; and the Virtual Astronomical Observatory (VAO, which is the operational phase of the National Virtual Observatory) will provide the infrastructure for cross-linking individual data archives. The widely used Virtual Solar Observatory provides the community with convenient data identification, search, and retrieval from most solar instruments.

The panel highlights the following issues:

  • Archives are most effective when they provide access to higher-level data products; this requires appropriate investment in data pipelines.

  • Systematically collected, well-calibrated data sets offer the greatest potential for broad scientific exploitation.

  • Developing an appropriately configured data archive requires deliberate investment of resources; established archives can incorporate new data sets without requiring substantial additional resources if the appropriate reduction and analysis pipelines are available.

  • There is no formal mechanism for obtaining long-term support for data archives extending beyond the operational timelines of surveys such as SDSS.

The panel recommends support for one or more data curation centers for ground-based data. The agencies should coordinate support for archive development and maintenance, so that observatories can focus their individual resources on data pipelines. Broad public access to data and data products must be a strong consideration when significant public funding is provided for private facilities.

The panel recommends an integrated ground-based astronomy data-archiving program starting at a level of ~$2 million per year for construction and ramping down to ~$1 million per year for ongoing operations costs.

Data Analysis Software Infrastructure

Astronomers use a variety of software tools on a diverse set of computer platforms to carry out their research. The past decade has seen significant developments using several common data analysis environments, including IRAF, IDL, and Python. Current and forthcoming OIR telescopes utilize instruments of increasing complexity and data volume, including multiobject spectrographs, integral field units, and optical interferometers. Development of dedicated software packages and specialized analysis techniques requires significant resources, but costs can be shared between observatories and users within commonly accepted environments.

The panel concluded that the provision of adequate software tools will be crucial to maximizing the scientific gains from community investment in new instrumentation for telescopes at all wavelengths.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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The panel recommends that resources should be invested to plan and develop common-use infrastructures that permit cooperative development of key software to support astronomical instrumentation.

Theoretical Astrophysics and OIR Astronomy

Theoretical astrophysics plays multiple pivotal roles in all OIR research activities. Theorists generate new ideas about the universe, provide the conceptual framework for observational discovery, and seek to synthesize a coherent world view of astrophysical phenomena. They mine large astronomical data sets and interpret pre-existing observations using sophisticated algorithms and modeling. They run supercomputer simulations that incorporate key physical processes and strive to provide a realistic imitation of reality. Theory guides the conception and design of new observational programs and surveys, posing specific questions to investigate and identifying crucial predictions for observers to confirm or refute. An increasingly large number of major breakthroughs in astronomy come from observations directly motivated by theory.

As examples, the LSST science theme to probe dark energy and dark matter will require detailed cosmological simulations to interpret the data. The same is true of GSMT investigation of the early generation of galaxies and the reionization of the universe. In the realm of helioseismology, theory and observations have repeatedly challenged each other to measure and understand better the flow patterns in the Sun and the way they generate magnetic-field variability.

The SFPs identified a number of key theoretical studies associated with almost all of the scientific themes defining the frontier of research in astronomy and astrophysics during the next decade.

The panel recommends a significant increase in the funding for theoretical astrophysics.

A subset of the new funding opportunities should be devoted to a new strategic theory program (STP). The STP will fund (1) investigations aimed at generating new observatory and mission concepts that address the science questions highlighted by the Astro2010 Science Frontier Panels and (2) more focused studies on behalf of observatories and missions that are approaching or have already entered the design phase.

The panel recommends a strategic theory program at ~$3 million per year.

High-Priority Continuing Activities

To maintain and enable a balanced and strong U.S. program in OIR astronomy during the 2010-2020 decade the panel assessed the level of NSF-AST support for continuing activities and recommends continued support at the current levels in two areas:

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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  • NSF should continue to support the National Solar Observatory (NSO) over the 2010-2020 decade to ensure that the Advanced Technology Solar Telescope (ATST) becomes fully operational. ATST operations will require a ramp-up in NSO support to supplement savings that accrue from the planned closing of current solar facilities.

  • Funding for NOAO facilities should continue at approximately the 2010 level.

In addition, the panel identified two continuing activities that need enhanced support in the coming decade: OIR astronomy grants programs and the Gemini Observatory.

OIR Astronomy Grants Programs

The highest-priority activities in the continuing category are the grants programs at NSF and at NASA—they are the lifeblood of U.S. astronomy. The individual grants program at NSF is particularly critical for the ground-based OIR enterprise, as in most cases there is not a direct connection between awards of telescope time and awards of funding to support people to analyze the data. In many cases, scientific progress is actually paced by the availability of labor for the analysis.

The grants program is the primary mechanism for pursuing a diverse portfolio of smaller projects. Such projects, whether from individuals or small teams, are a highly effective investment, as one can maximize the use of competitive selection and avoid the encumbrances and management overheads of larger projects. In a time when astronomical facilities are growing in scope, the grants program is the principal counterbalance to maintain a culture for the field in which new, riskier ideas can flourish and individuals can tailor a science program based on multiple data sets. Scientific research proceeds as much from punctuated breakthroughs as from persistence, and astronomy would be at great risk if individual investigations were diminished in emphasis.

The grants program is also critical for the development of the next generation of astronomers and instrumentalists. In addition to the student and postdoctoral support and mentoring provided on project grants, funding for conferences, focused schools, and other programs can be handled through a nimble small-grants program.

The panel concluded that the individual grants programs at all agencies are as critical as ever.

The panel recommends that the NSF-AST grants program (AAG) should be increased above the rate of inflation by ~$40 million over the decade to enable the community to utilize the scientific capabilities of the new projects and enhanced OIR system.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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The Gemini Observatory

The second high-priority continuing activity for OIR astronomy is the Gemini Observatory, which provides on a competitive basis the largest number of nights on 8-m telescopes that are open to the general U.S. community. The Gemini Observatory, properly instrumented, can address many of the science questions identified by the Science Frontiers Panels and provide ground-based spectroscopic follow-up for LSST discoveries and support for space missions.

The Gemini Observatory, however, is a partnership of seven nations, with the 51.12 percent U.S. share representing the bulk of community open access to large apertures. The complex management structure that has evolved from the international nature of the Gemini partnership prevents the U.S. National Gemini Office from serving as an advocate for U.S. interests at a level commensurate with its partnership share. The ALTAIR report found community dissatisfaction with its current instrumentation (dominated by narrow-field infrared capabilities), its operation model emphasizing queue observing, and the lack of transparency of its governance.

The Gemini Observatory should be viewed as an integral component of the U.S. telescope system. Specifically, Gemini would be more effective with a stronger connection between observatory management and the U.S. community. The renegotiation of the international Gemini agreement in 2012 will provide an opportunity to simplify management to achieve these goals while still respecting the sensitivities of the international partners. In addition, the NSF-AST senior review and internal Gemini reviews, have noted that Gemini operations costs are high compared to those of other national facilities and the nonfederal observatories. A Gemini Observatory better integrated with the U.S. system and its resources could streamline operations. Although the panel has no means to estimate the savings that could be realized, decreased operating costs could provide a means to augment the U.S. Gemini share if the opportunity arose and if the Gemini Observatory were seen as more representative of U.S. interests.

Continued support for Gemini operations into the next decade is a priority in maintaining a balanced OIR research program. The panel recommends that the following actions be taken to enhance Gemini’s contribution to the U.S. OIR system:

  1. The governance of the international Gemini Observatory should be restructured, in collaboration with all partners, to improve the responsiveness and accountability of the observatory to the goals and concerns of all its national user communities. Project share should be an important factor in the development of strategic plans. U.S. participants in governance (for example, Gemini Board representatives) should be selected with the goal of accurately representing the broad interests of the U.S. OIR system.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
  1. NSF and its international partners should convene an independent panel to solicit detailed advice from management experts, existing observatories, instrument builders, experienced Gemini users, and other parties on the design of the new Gemini governance and management structure.

  2. As part of the restructuring negotiations, the United States should attempt to secure an additional fraction of the Gemini Observatory, including a proportional increase in the U.S. leadership role. The funding allocated for any augmentation in the U.S. share should be at most 10 percent of FY2010 U.S. Gemini spending.

  3. The United States should also seek improvements to the efficiency of Gemini operations. Efficiencies from streamlining Gemini operations, possibly achieved through a re-forming of the national observatory to include NOAO and Gemini under a single operations team, should be applied to compensate for the loss of the United Kingdom from the Gemini partnership, thereby increasing the U.S. share.

  4. The panel recommends that the United States support the development of medium-scale, general-purpose Gemini instrumentation and upgrades at a steady level of about 10 percent of the U.S. share of operations costs. U.S. support for new large Gemini instruments (>~$20 million ) should be competed against proposals for other instruments in the recommended mid-scale instrumentation program—a program aimed at meeting the needs of the overall U.S. system discussed elsewhere in this panel report.

Additional Activity

During its work the OIR Panel identified an additional activity with significant potential importance: optical and infrared astronomy in Antarctica.

New sites for astronomical observations in Antarctica that are located away from the U.S. facilities at the South Pole hold significant promise. The unique climate and weather of Antarctica offer extraordinary opportunities for OIR observations. While submillimeter observations have been executed successfully from the South Pole, the best sites for OIR work are being explored at high-altitude plateau sites such as Dome C. Promising results for unusually dark IR skies and for excellent seeing above a low-lying ground layer are being investigated by international programs based in Europe, Australia, and China. For some applications, the potential exists to rival space and airborne platforms for science in long-wave IR astronomy and OIR interferometry. Despite the rich scientific potential of these sites, no significant U.S. site development plans exist. NSF is the lead agency for scientific work in Antarctica, but NSF-AST and the NSF Office of Polar Programs need to work collaboratively to facilitate the best overall scientific program for the continent, including improving the site assessments and potentially establishing a presence on the plateau sites, either through partnership or on our own.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

The panel recommends internal coordination at NSF to encourage U.S. investigators to participate in the development of the new, and potentially revolutionary, arena for OIR astronomy represented by excellent observing sites in Antarctica.

OIR Astronomy and Demographics

The panel’s charge emphasizes the need to recommend a balanced program for OIR for the next decade. The programs highlighted above strike that balance in terms of the division between large, medium, and small-scale projects, but most importantly in balancing the access to these projects and facilities across the complete astronomical demographic. Central to the panel’s recommendations is an endorsement and strengthening of the U.S. telescope system providing widespread access to the full range of telescope apertures and capabilities, as well as ensuring public access to GSMTs and LSST, the large-project recommendations of this panel, which are integral components of this system. This level playing field, particularly in the context of a vigorous AAG program, invites and enables the growth of those with budding astronomical interests. Sky surveys, such as LSST, create databases as accessible to high-school students as they are to professional researchers at well-endowed institutions. The Astro2010 survey’s Infrastructure Study Group for demographics noted the severe underrepresentation of minorities in astronomy. A strong, diverse U.S. system—with investment at all aperture sizes and with emphasis on surveys and data archiving—provides scientific opportunities to engage entry-level students in research, and to retain them in the career-development pipeline, at virtually any institution during their undergraduate years. The demographics group also noted that training of the next generation of instrumentalists may be at risk, particularly with the dominance of large-scale projects limiting opportunities for hands-on end-to-end training on projects of modest scale. The expanded TSIP, and particularly ReSTAR, instrumentation opportunities inherent in the recommendations above directly address this need and ensure the continued existence of innovative and flexible instrumentation programs at federal and nonfederal institutions alike.

Interagency Collaboration

As the principal agency supporting ground-based OIR astronomy in the United States, NSF should continue to lead the federal efforts for the OIR system as described in this section and work with DOE as it becomes increasingly involved in system activities. In addition, NASA should be engaged as a full collaborator in supporting the construction, operation, and analysis activities of ground-based OIR facilities where such joint interchange will advance the science and programmatic objectives of both agencies.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

RECOMMENDED PRIORITIES AND PLAN FOR THE NEXT DECADE

This section presents (1) a summary of the conclusions for the activities described above in “Future Programs in OIR Astronomy”; (2) the recommended priorities; and (3) a prioritized implementation approach for the next decade for the budget guidelines provided by Astro2010.

Conclusions and Recommendations for Large Programs

Having considered proposals from the research community for new large facilities, the OIR Panel reached the following conclusions for large programs:

  • The science cases for a 25- to 30-m Giant Segmented Mirror Telescope and for the proposed Large Synoptic Survey Telescope are even stronger today than they were a decade ago.

  • Based on the relative overall scientific merits of GSMT and LSST, the panel ranks GSMT higher scientifically than LSST, given the sensitivity and resolution of GSMT.

  • Both GSMT and LSST are technologically ready to enter their construction phases in the first half of the 2010-2020 decade.

  • The LSST project is in an advanced state and ready for immediate entry into NSF’s MREFC line for the support of construction. In addition, the role of DOE in the fabrication of the LSST camera system is well defined and ready for adoption.

  • LSST has complementary strengths in areal coverage and temporal sensitivity to GSMT, with its own distinct discovery potential. Indeed, GSMT is unlikely to achieve its full scientific potential without the synoptic surveys of LSST. Consequently LSST plays a crucial role in the panel’s overall strategy.

  • GSMT is a versatile observatory that will push back today’s limits in imaging and spectroscopy to open up new possibilities for the most important scientific problems identified in the Astro2010 survey. This exceptionally broad and powerful ability over the whole range of astrophysical frontiers is the compelling argument for building GSMT.

  • Given the development schedules for GSMT and in order to ensure the best science return for the U.S. public investment, it is both vital and urgent that NSF identify one U.S. project for continued support to prepare for its entry into the MREFC process.

Based on these conclusions, the panel recommends the following ordered priorities for the implementation of the major initiatives that form part of its recommended OIR research program for the 2010-2020 decade:

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
  1. Given the panel’s top ranking of the Giant Segmented Mirror Telescope based on its scientific merit, the panel recommends that the National Science Foundation establish a process to select which one of the two U.S.-led GSMT concepts it will continue to support in its preparation for entry as soon as practicable into the MREFC line. This selection process should be completed within 1 year from the release of this panel report.

  2. The panel recommends that NSF and DOE commit as soon as possible, but no later than 1 year from the release of this report, to supporting the construction of the Large Synoptic Survey Telescope. Because it will be several years before either GSMT project could reach the stage in the MREFC process that LSST occupies today, the panel recommends that LSST should precede GSMT into the MREFC approval process. The LSST construction should start no later than 2014 in order to maintain the project’s momentum, capture existing expertise, and provide critical synergy with GSMT.

  3. The panel recommends that NSF, following the completion of the necessary reviews, should commit to supporting the construction of its selected GSMT through the MREFC line at an equivalent of a 25 percent share of the total construction cost, thereby securing a significant public partnership role in one of the GSMT projects.

  4. The panel recommends that in the longer term NSF should pursue the ultimate goal of a 50 percent public interest in GSMT capability, as articulated in the 2001 decadal survey (Astronomy and Astrophysics in the New Millennium). Reaching this goal will require (most likely in the decade 2021-2030) supporting one or both of the U.S.-led GSMT projects at a cost equivalent to an additional 25 percent GSMT interest for the federal government. The panel does not prescribe whether NSF’s long-term investment should be made through shared operations costs or through instrument development. Neither does the panel prescribe whether the additional investment should be made in the selected MREFC-supported GSMT in which a 25 percent partnership role is proposed already for the federal government. But the panel does recommend that, in the long run, additional support should be provided with the goal of obtaining telescope access for the U.S. community corresponding to total public access of 50 percent of a GSMT.

The panel has chosen not to prescribe in this report a process by which NSF could choose between the GSMT projects for a federal investment. However, the panel would expect such a process to include the setting and application of criteria by a committee of U.S. researchers (with the possible participation of non-OIR astronomers and researchers from other fields cognizant of the challenges of implementing billion-dollar-class facilities), as well as a thorough and independent assessment of cost and technical and schedule risk.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×
Conclusions and Recommendations for Medium and Small Programs

The panel concluded that mechanisms are limited or non-existent for funding major instruments and projects with costs above the funding guidelines of standard programs such as the NSF AST or MRI programs but below the level of the NSF-wide MREFC.

  • The panel recommends as its highest-priority medium activity a new medium-scale instrumentation program in NSF’s AST that supports projects with costs between those of standard grant funding and those for the MREFC line. To foster a balanced set of resources for the astronomical community, this program should be open to proposals to build (1) instruments for existing telescopes and (2) new telescopes across all ground-based astronomical activities, including solar astronomy and radio astronomy. The program should be designed and executed within the context of, and to maximize the achievement of, science priorities of the ground-based OIR system. Proposals to the medium-scale instrumentation program should be peer reviewed. OIR examples of activities that could be proposed for the program include massively multiplexed optical/near-IR spectrographs, adaptive optics systems for existing telescopes, and solar initiatives following on from the Advanced Technology Solar Telescope. The panel recommends funding this program at a level of approximately $20 million annually.

The panel concluded that the Telescope System Instrumentation Program represents a successful model for enhancing federal and nonfederal telescope facilities while providing expanded public access to nonfederal facilities. The panel concluded further that TSIP, given sufficient resources, has the potential to help configure and balance the overall U.S. OIR system to maximize the efficiency of observing resources while providing instruments that will enable observations at the limits of current technology.

  • As its second-highest-priority medium activity, the panel recommends enhancing the support of the OIR system of telescopes by (1) increasing the funds for the Telescope System Instrumentation Program and (2) adding support for the small-aperture telescopes into a combined effort that will advance the capabilities and science priorities of the U.S. ground-based OIR system. The OIR system includes telescopes with apertures of all sizes, whereas the TSIP was established to address the needs of large telescopes. The panel recommends an increase in the TSIP budget to approximately $8 million (FY2009) annually. Additional funding for small-aperture telescopes in support of the recommendations of the National Optical Astronomy Observatory (NOAO) Renewing Small Telescopes for Astronomical Research (ReSTAR) committee (approximately $3 million per year) should augment the combined effort to a total of approximately $11 million (FY2009) to encompass

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

all apertures. The combined effort will serve as a mechanism for coordinating the development of the OIR system. To be effective, the funding level and funding opportunities for this effort must be consistent from year to year. Although it is possible that the total combined resources could be administered as a single program, the implementation of such a program raises difficult issues, such as formulas for the value of resources or the need to rebuild infrastructure. The panel considers the administration of two separate programs under the umbrella of “system development” to be a simpler alternative. The expanded TSIP and the mid-scale instrumentation program both provide opportunities to direct these instrumentation funds strategically toward optimizing and balancing the U.S. telescope system.

  • The U.S. system of OIR telescopes currently functions as a collection of federal and nonfederal telescope resources that would benefit from collaborative planning and management—for example, to avoid unnecessary instrument duplication between telescopes. The panel recommends that NSF ensures that a mechanism exists, operating in close concert with the nonfederal observatories, for the management of the U.S. telescope system. The panel recommends that a high priority be given to renewing the system of ground-based OIR facilities, requiring a new strategic plan and a broadly accepted process for its implementation.

The panel concluded that initiating a tactical set of small targeted programs ($1 million to $3 million per year each) would greatly benefit ground-based OIR science in the coming decade and provide critical support for some of the medium and large programs.

  • The panel recommends the small programs in the following, unprioritized list:

    • An adaptive optics technology development program at the $2 million to $3 million per year level;

    • An interferometry operations and development program at a level of approximately $3 million per year;

    • An integrated ground-based-astronomy data-archiving program starting at a level of approximately $2 million per year and ramping down to approximately $1 million per year; and

    • A “strategic theory” program at the level of approximately $3 million per year.

Recommendations for Continuing Activities

The panel makes the following recommendations for continuing activities:

  • NSF should continue to support the National Solar Observatory (NSO) over the 2010-2020 decade to ensure that the Advanced Technology Solar Telescope

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

(ATST) becomes fully operational. ATST operations will require a ramp-up in NSO support to supplement savings that accrue from the planned closing of current solar facilities.

  • Funding for NOAO facilities should continue at approximately the FY2010 level.

  • The governance of the international Gemini Observatory should be restructured, in collaboration with all partners, to improve the responsiveness and accountability of the observatory to the goals and concerns of all its national user communities. As part of the restructuring negotiations, the United States should attempt to secure an additional fraction of the Gemini Observatory, including a proportional increase in the U.S. leadership role. The funding allocated for any augmentation in the U.S. share should be at most 10 percent of FY2010 U.S. Gemini spending. The United States should also seek improvements to the efficiency of Gemini operations. Efficiencies from streamlining Gemini operations, possibly achieved through a reforming of the U.S. national observatory to include NOAO and Gemini under a single operations team, should be applied to compensate for the loss of the United Kingdom from the Gemini partnership, thereby increasing the U.S. share. The United States should support the development of medium-scale, general-purpose Gemini instrumentation and upgrades at a steady level of about 10 percent of the U.S. share of operations costs. U.S. support for new large Gemini instruments (greater than approximately $20 million) should be competed against proposals for other instruments in the recommended mid-scale instrumentation program—a program aimed at meeting the needs of the overall U.S. OIR system discussed elsewhere in this panel report.

  • The NSF-AST grants program (Astronomy and Astrophysics Research Grants [AAG]) should be increased above the rate of inflation by approximately $40 million over the decade to enable the community to utilize the scientific capabilities of the new projects and enhanced OIR system.

  • NSF-AST should work closely with the NSF Office of Polar Programs to explore the potential for exploiting the unique characteristics of the promising Antarctic sites.

Implementation Plan

The supplement at the end of this report presents an implementation plan for the panel’s recommendations for the projects and activities summarized in this section. The plan is consistent with the historical funding pattern for NSF-AST and fits within the budgetary planning guideline provided by the Astro2010 Survey Committee.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

SUMMARY COMMENTS

In this report the panel presents a balanced program for U.S. OIR astronomy that is consistent with historical federal funding of the field. More importantly, the program recommended will enable astronomers to answer the compelling science questions that can now be formulated, and it will open new windows of discovery for the future. The two large projects recommended, GSMT and LSST, will each advance fundamentally important observing capabilities by one or two orders of magnitude beyond the present. Together, they address the core of astronomy and astrophysics, including 18 of the 20 science questions and all 5 of the discovery areas identified by the Astro2010 Science Frontiers Panels. The OIR Panel’s two medium-scale recommendations address clear gaps in the current approach and will support a range of specialized instruments and telescopes that will provide a variety of tools to address central science questions from many angles and to strengthen the overall U.S. system of OIR telescopes. The panel values the small-scale programs because they advance OIR science and provide essential support for the medium- and large-scale activities. OIR astronomy has an exceptionally complex administrative structure. The panel believes that this can be turned to advantage through an increased emphasis on partnerships that include NSF, DOE, and NASA; U.S. federal, state, and private institutions; and international partners. The scale of the new large projects demands cooperation: if this task is approached with imagination and good will, we can gain from the key capabilities that each partner brings.

The revolution in human understanding that began with Galileo’s telescope 400 years ago has not slowed down or lost its momentum—in fact it is accelerating. This panel has identified the most promising areas for the United States to invest in right at the center of a thriving scientific adventure. It looks forward to the rich flow of science that will come from implementing these recommendations.

SUPPLEMENT: IMPLEMENTING THE PANEL’S RECOMMENDATIONS WITHIN THE PROJECTED FUNDING CONTEXT

The NSF Division of Astronomical Sciences (NSF-AST) is the federal steward and principal source of federal funding for ground-based OIR astronomy in the United States. NASA provides some support for ground-based efforts in connection with its space missions (e.g., partial support of Keck, IRTF, and interferometry). DOE is becoming an increasingly important source of funding, as the scientific interests of high-energy physics and cosmology become deeply interconnected. Here the panel concentrates on NSF funding because of its central importance to

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

ground-based funding and because it is the primary source for most of the projects and efforts under consideration by the panel.

As stated above in the section “Interagency Collaboration” at the end of the section “Future Programs in OIR Astronomy,” NSF should continue to lead the federal efforts for the OIR system and work with DOE as it becomes increasingly involved in system activities. In addition, NASA should be engaged as a full collaborator supporting construction, operation, and analysis activities of ground-based OIR facilities where such joint interchange will advance the science and programmatic objectives of both agencies.

Total Costs and Schedules for Large Projects

The technical, cost, and schedule risks for the large projects are described in “Large Programs” under “Future Programs in OIR Astronomy.” For ease of reference, Table 7.5 provides a summary of the construction and operations costs and construction schedules provided by the individual projects and the results of the

TABLE 7.5 Summary of Estimates of Construction and Operations Costs (FY2009 dollars) and Schedule Estimates for OIR Large Projects

Project

Project-Identified Values

CATE Valuesa

Cost Appraisal

Reserve

Total

Operations Costs per Year

Construction Schedule (months)

Construction Schedule (months)

Cost Analysis

Cost Sensitivity 70% value

LSST

$354M

$102M

$456M

$41M

97

112

$398Mb

n/a

GMT

$563M

$113M

$676M

$37Mc

128

178

n/a

$1.1Bd

TMT

$760M

$227M

$987M

$54Me

168

191-239f

n/a

$1.4Bd

aThe calibration data available for ground-based projects were less than those available for space-based projects; this was a limiting factor in the independent cost appraisal and technical evaluation (CATE) assessment, particularly for the two GSMT projects. The methodology is discussed in more detail in the section “Opportunities in OIR Science” of this panel report. It is important to note that this is a cost-sensitivity analysis rather than a cost appraisal, showing the effects of cost variations in key subtasks.

bFor LSST, the cost appraisal was based on applying a parametric model to a level-3 work breakdown structure submitted by project personnel, including optics and facility fabrication. The cost appraisal did not examine instrument or data-handling costs, and this estimate does not include operation costs. The independent CATE assessment produced a single cost appraisal for LSST, and so no distribution is noted here.

cIncludes instrument and facility upgrades of $16 million per year.

dFor the two GSMTs, cost-sensitivity analysis was restricted primarily to the costs of manufacturing the optics (discussed in the section “Opportunities in OIR Science”) and the science instruments (assumed to increase by ~100 percent based on the contractor’s experience with space missions). The independent CATE assessment produced a cost-sensitivity distribution for the GSMTs, and costs at 70 percent confidence levels are given here.

eIncludes instrument upgrades of $20 million per year.

fRange of values reflects the independent contractor’s assessment of schedule uncertainty for fabrication of the primary mirror segments.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

assessment of the independent contractor. All projects explained the methodology and basis for their estimates and the basis for a reserve (contingency) amount that they included in their total. The independent CATE process utilized the information provided by the projects and its own methods and data to develop independent assessments for costs, risks, and schedules.

The available calibration data for ground-based projects were less than those available for space-based projects; this was a limiting factor in the independent CATE assessment, particularly for the two GSMT projects. The independent CATE assessment also estimated schedule risk in all three projects, and these values are listed in Table 7.5.

The panel concluded that both GSMT projects involve a substantial risk to cost and/or schedule that need to be carefully examined and considered as NSF executes a process to select a potential partner for public investment. It is likely that such a commitment would have to be sustained for more than a decade prior to the completion of commissioning and initial scientific utilization of a GSMT concept by the community. The panel notes and endorses the NSF procedure for obtaining detailed cost and schedule estimates as part of its Major Research Equipment and Facilities Construction (MREFC) process.

Proposed NSF Share of Large Project Costs

It is important to note that none of the three large projects recommended by the OIR Panel is requesting full support from NSF. The LSST project has developed a proposed cost-sharing plan involving NSF, DOE, and other partners. GMT and TMT also have other partners, and the panel assumed NSF participation at the 25 percent level. Table 7.6 shows the proposed cost to NSF for the large projects, based on the total values shown in Table 7.5.

Large Projects and MREFC Opportunities

The construction costs of the GSMT and LSST projects recommended by the panel are of a scale that an NSF investment in construction will come from the agency’s MREFC program. This program supports the construction of new major

TABLE 7.6 Proposed NSF Share of Costs of Construction of Large Projects (FY2009 dollars)

Project

NSF Share

Notes

LSST

$261 to $298M

Balance from DOE and other sources

GMT

$169 to $250M

25% share for NSF, balance from other partners

TMT

$247 to $325M

25% share for NSF, balance from other partners

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

equipment and facilities with costs that exceed the capabilities of a single NSF division and require investments on an NSF-wide basis.

Both GSMT and LSST have advanced to the stage at which they can be considered for construction and operations funding during the period covered by Astro2010. LSST is already placed in the final preparatory stages of the MREFC approval process.

While the MREFC line offers the primary opportunity for implementing federal support for these two large projects in the coming decade, there are significant factors beyond the requirements of MREFC that enter into the planning process. First, both GSMT projects will involve funding and partnering outside of NSF. GMT and TMT are established as private, nonfederal projects with international components. Second, LSST is to be a partnership with DOE and also utilizes private, nonfederal resources. Third, MREFC does not cover operating costs, which will be significant over the lifetime of the projects and will have to be covered by NSF-AST and the partners in the projects. The plans presented below account for both proposed MREFC funding and the projected operating costs to be borne by NSF-AST. The assumed total MREFC funding for GSMT and LSST combined is consistent with the inflation-adjusted MREFC funding for ALMA.

LSST Funding

The panel notes that the LSST project has advanced to the final design phase, which will take it to the point of readiness for construction and also prepare it for the NSF critical design review. As noted above, this panel report recommends that NSF should commit to supporting the construction of LSST, with construction starting no later than 2014 in order to maintain the project’s momentum, capture existing expertise, and achieve critical synergy with GSMT.

The level of NSF support requested by the project would be $298.5 million. The Department of Energy would provide support in the form of construction of the LSST camera system, with some support coming from other sources. LSST operations costs (projected at $40 million per year) would be split evenly among NSF, DOE, and an additional partner.6

GSMT Funding

The panel reaffirms the goal of the previous decadal survey, Astronomy and Astro physics in the New Millennium, of a 50 percent public share of a GSMT. However, the panel recognizes that the projected availability of public funding will re-

6

The additional partner was not identified to the panel in the documentation provided to it by the LSST project.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

quire a distributed investment over more than the present decade to reach that goal. The panel believes that a 50 percent public share of a GSMT is in the best interest of the nation, maximizing the scientific yield of the OIR system and GSMT itself. Below, the panel outlines one possible scenario to achieve this objective, although of course other approaches exist.

Elsewhere in this report, the panel recommends that the U.S. government become a full partner in a GSMT project at the 25 percent level as soon as possible and that NSF should establish a process to choose which of the two U.S.-led GSMT concepts will receive a founding-member public investment.

After selection, negotiations to establish U.S. participation can begin and the particular mechanisms and commitments worked out. The investment made by NSF should ensure a significant and ongoing public role in the governance and operation of the chosen telescope. The panel’s preferred mechanism is to support this participation through the MREFC process; 25 percent of a GSMT (approximately $250 million in FY2009 dollars) is consistent with a typical MREFC funding envelope, and significantly below U.S. ALMA participation. NSF-AST would also support operations at a level consistent with its share (25 percent of total costs.) Alternatively, the balance between operations and construction funding could be negotiated as part of the initial buy-in.

In the case of 7 percent per year AST budget growth over the decade,7 additional participation, most likely in the other GSMT project, could be done through the NSF-AST budget process, providing support for instrumentation and possibly construction. This could be done either formally through a negotiated participation or through a substantially expanded TSIP-like program. The goal would be a 25 percent share in observing time in the other GSMT, but without a formal governance role.

Funding Profile for the 2010-2020 Decade

Table 7.7 and Figure 7.19 show (as an existence proof) a representative overall budget profile for this panel’s OIR recommendations that follows guidelines provided by the Program Subcommittee of the Astro2010 Survey Committee. The guidelines assume 3.7 percent per year growth above inflation for the NSF-AST budget for the years beyond the currently known or projected values and also take into account the continuing costs of existing AST programs such as grants, national centers, instrumentation, and special projects. The OIR plan described in Table 7.7 and Figure 7.19 is for the continuing and new funds for OIR activities that are projected to become available during the decade.

7

This level of increase is consistent with NSF-AST keeping pace with a doubling of the NSF budget.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
×

TABLE 7.7 Budget Profile for Panel’s OIR Recommendations

Activities

Funds for the Decade (FY2009 dollars)

Large Activities

Requested from MREFC; see Table 7.6

Medium Activities (in priority order)

Mid-scale instruments and projects

$190M

TSIP and ReSTAR

$106M ($76M + $30M)

Small Activities (alphabetical order)

Adaptive optics development program

$18M

Ground-based archive

$14M

Interferometry operations and technology development

$27M

Strategic theory

$26M

Continuing Activities

NSF-AST research grants program (AAG)

$490M (includes $40M increase)

Gemini operations and instrumentation

$250M (increases U.S. funding by 10%)

NOAO operations

$260M

NSO ATST increase

$117M (includes $26M increase to support LSST)

Large Projects Operations and Additional GSMT Share (in priority order)

NSF share of LSST and GSMT operations resulting from MREFC investments

$83M ($14M/year and $8M/year)

Additional GSMT share

$97M (construction or instrumentation support to acquire additional share)

FIGURE 7.19 Chart showing straw-man scenario for overall NSF-AST spending, assuming 3.7 percent real growth per year.

FIGURE 7.19 Chart showing straw-man scenario for overall NSF-AST spending, assuming 3.7 percent real growth per year.

Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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Suggested Citation:"7 Report of the Panel on Optical and Infrared Astronomy from the Ground." National Research Council. 2011. Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics. Washington, DC: The National Academies Press. doi: 10.17226/12982.
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Panel Reports—New Worlds, New Horizons in Astronomy and Astrophysics Get This Book
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Every 10 years the National Research Council releases a survey of astronomy and astrophysics outlining priorities for the coming decade. The most recent survey, titled New Worlds, New Horizons in Astronomy and Astrophysics, provides overall priorities and recommendations for the field as a whole based on a broad and comprehensive examination of scientific opportunities, infrastructure, and organization in a national and international context.

Panel Reports--New Worlds, New Horizons in Astronomy and Astrophysics is a collection of reports, each of which addresses a key sub-area of the field, prepared by specialists in that subarea, and each of which played an important role in setting overall priorities for the field. The collection, published in a single volume, includes the reports of the following panels:

  • Cosmology and Fundamental Physics
  • Galaxies Across Cosmic Time
  • The Galactic Neighborhood
  • Stars and Stellar Evolution
  • Planetary Systems and Star Formation
  • Electromagnetic Observations from Space
  • Optical and Infrared Astronomy from the Ground
  • Particle Astrophysics and Gravitation
  • Radio, Millimeter, and Submillimeter Astronomy from the Ground

The Committee for a Decadal Survey of Astronomy and Astrophysics synthesized these reports in the preparation of its prioritized recommendations for the field as a whole. These reports provide additional depth and detail in each of their respective areas. Taken together, they form an essential companion volume to New Worlds, New Horizons: A Decadal Survey of Astronomy and Astrophysics. The book of panel reports will be useful to managers of programs of research in the field of astronomy and astrophysics, the Congressional committees with jurisdiction over the agencies supporting this research, the scientific community, and the public.

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