A Strategy for Ground-Based Optical and Infrared Astronomy

The panel first summarizes briefly the recommendations of the AASC report regarding OIR astronomy and the new developments that have occurred since that report was written.

Substantial progress has been made toward achieving the AASC report's recommendations for new facilities in OIR astronomy. For major new ground-based facilities, the first-priority recommendation was for an infrared-optimized 8-meter telescope on Mauna Kea in Hawaii, and the third-priority recommendation was for a Southern Hemisphere 8-meter telescope. (The second priority was for the Millimeter Array.) The NSF responded to these recommendations through a commitment to support 50% of the international Gemini project. Two 8-meter Gemini telescopes are currently under construction; Gemini North (Plate 1) is scheduled to be fully operational in 2000, and Gemini South in 2003.

For moderate ground-based facilities, the first-priority recommendation of the AASC report was to develop adaptive optics facilities to reduce image distortion by atmospheric turbulence. The NSF has responded to this recommendation by increasing substantially its funding of adaptive optics instrumentation. This effort enjoys major contributions from the Department of Defense, which has undertaken to declassify its advanced technology for adaptive optics, and from the Department of Energy. These agencies support very promising programs in laser guide star technology at the Air Force Phillips Laboratory and the Lawrence Livermore National Laboratory, respectively. The potential scientific yield of adaptive optics technology is enormous. Most of the work to develop and deploy this technology remains to be done; but, as the recent infrared images of the impact of comet Shoemaker-Levy 9 with Jupiter demonstrate, astronomers are already beginning to realize the benefits.

The AASC report's second-priority recommendation for moderate ground-based facilities was for the development of facilities and technology for OIR interferometry. The NSF has responded to this recommendation by increasing its support of technology development for this area. The twin 10-meter Keck telescopes on Mauna Kea, the first of which is now operational and the second of which is currently under construction, will provide a major new facility for OIR interferometry.

The AASC report's third-priority recommendation for moderate ground-based facilities was for the construction of several new 4-meter-class telescopes, supported insofar as possible through a combination of federal, state, and private funds. Substantial progress has been achieved toward this goal with the successful completion of the 3.5-meter ARC telescope at Apache Point, New Mexico, operated by a consortium of state and private institutions and funded partially by the NSF, and the 3.5-meter Wisconsin-Indiana-Yale-NOAO (WIYN) telescope at Kitt Peak National Observatory (KPNO), constructed and operated by a consortium of private and state universities and the NOAO. These excellent telescopes are demonstrating the high scientific performance enabled by new technologies and the financial efficiency of cost-sharing arrangements. More such telescopes are needed, however, most urgently in the Southern Hemisphere.

The AASC report's highest-priority recommendation for ground-based astronomy was not for new facilities, however. It was for the "strengthening of the infrastructure for research, that is, increased support for individual research grants and for the maintenance and refurbishment of existing frontier equipment at the national observatories" (pp. 12-13). In particular, the AASC report recommended that "the NSF should include appropriate financial provision for operation of any new telescope in the plan for that facility," and that "individual research grants be increased to an adequate and stable fraction of the NSF's total operations budget for astronomy. In order to gather and analyze the large amounts of data that will become available with new instrumentation, to allow young researchers to take advantage of the new opportunities for discovery, and to restore support for theoretical astrophysics, the individual grants budget should be increased by $10 million per year" (pp. 13-14).

The NSF Division of Astronomical Sciences has not yet been able to implement fully this paramount recommendation of the AASC report. Moreover, the NSF will find it impossible to address this recommendation or the remaining recommendations for new facilities without an increase in the net funding for astronomy. For example, sufficient funds for the support of the infrastructure of other unique facilities, such as the National Radio Astronomy Observatory's (NRAO) Very Long Baseline Array (VLBA) and Very Large Array (VLA), have not materialized, and these instruments are currently operating in a less than optimal fashion.

A major problem for the NSF is to identify the funds required to operate the U.S. share of the IGP without encroaching on individual research grants or impacting the operations of other important facilities. To do this in a constrained budget scenario will require a further focusing of priorities and resources at NOAO. While NOAO might achieve further efficiencies, certain telescope-instrument combinations would probably have to be closed if NOAO were required to absorb the full cost of the U.S. share of Gemini operations. Furthermore, NOAO's ability to develop new instruments and telescopes and to meet the observing needs of the nation's astronomers would be seriously impaired by such a requirement.

Figure 1. Distribution of NSF Division of Astronomical Sciences 1994 funding ($M; total is approximately $105 M).

Figure 2 shows the history of funding of astronomy research by the NSF in the decade from 1985 to 1994. The net funding (in constant 1994 millions of dollars, corrected for inflation) decreased by about 5% from 1985 to 1990, then increased to a maximum in 1992 of about $118 M (excluding Gemini construction), or about $130 M (including Gemini), and has decreased thereafter. The funding of astronomy, as a fraction of the total NSF Mathematical and Physical Sciences Directorate budget, has decreased from 19.3% in 1984 to 17.2% in 1994, excluding major capital construction projects such as Gemini. Including them, the fraction has decreased from 19.3% to 18.4% during the same decade.

Figure 2. History of funding of NSF Division of Astronomical Sciences from 1985 to 1994. Funding primarily for radio astronomy, including NRAO, NAIC, and the independent radio observatories, is shown in red. The NRAO wedge includes funds for construction of the VLBA but not the $75 M funding appropriated by Congress in 1989 for construction of the Green Bank telescope. The NAIC wedge includes funds for the Arecibo telescope upgrade. Funding primarily for OIR astronomy, including the ATI program, NOAO (including solar astronomy), and Gemini construction, is shown as yellow. Funding of grants to individual investigators, including grants for OIR astronomy but excluding grants for the ATI program and the independent radio observatories, is shown as light blue.

Some redistribution of funding within the NSF Division of Astronomical Sciences budget is evident in Figure 2. The rapid decrease in the NRAO budget after 1992 may be attributed to the termination of funding for construction of the VLBA. Excluding VLBA construction, the NRAO operating budget increased by about 23%, from $23.6 M in 1985 to $29.0 M in 1994. The NOAO budget, excluding Gemini construction but including the GONG project, decreased by about 10%, from $30.5 M in 1985 to $27.5 M in 1994. The funding of grants to individual investigators decreased by approximately 18%, from $25.8 M in 1985 to $21.1 M in 1993, but was restored in 1994 to $25.0 M, 3% less than the 1985 level. The two most significant qualitative changes are the increase by a factor 3.5 of the budget for the ATI program, from approximately $2.5 M in 1985 to $8.7 M in 1994, and the construction budget for the international Gemini project.

As noted by the AASC report, the shortage of funding to support research by individual investigators has become acute. This remains true despite the fact that the NSF grants program was restored in 1994 to approximately the 1985 level, because the number of astronomers (measured either by the number of members of the American Astronomical Society or by the number of papers published in the Astrophysical Journal and the Astronomical Journal) has increased by approximately 40% during the same decade. (Much of this growth can be attributed to rapid growth of NASA programs in space astrophysics.) Astronomy is a growing science, and that has resulted in keener competition, both for research grants and for access to facilities at the national observatories.

The IGP is intended to support only the management, operations, facilities, and instrumentation development for the telescopes themselves. Each participating nation is expected to provide for the research needs of its own astronomers who will use the Gemini telescopes, including travel, data archiving and distribution, and limited support for instrumentation development. The NOAO is planning to redirect its internal resources to support these activities through the U.S. Gemini Project Office (USGPO) and has estimated that the cost to do so will rise to approximately $2.5 M by 2003. With level funding, NOAO can support U.S. scientific access to Gemini only by reducing support of other activities that it currently supports.

Figure 3. U.S. funding of Gemini operations, showing the U.S. 50% commitment for operations of the Gemini telescopes through the IGP and also the cost estimated by NOAO for the USGPO to support U.S. scientific access.

Table 1. NOAO Telescopes and Oversubscription Rates

	Telescope	Focal Ratios	Nights Scheduled Feb. 1994-Jan. 1995	Oversubscription Rate by Nights Feb. 1994-Jan. 1995 (dark/bright)
Kitt Peak National Observatory	4-m	2.7/8/15	278	3.0/2.0
	3.5-m WIYN	6.9
	2.1-m	7.5/15	286	2.5/2.0
	1.3-m	15	260	1.5
	0.9-m	7.5/13.5	274	2.0/1.9
	0.9-m Coude' Feed	31	258	1.2
	0.6/0.9-m Schmidt	3.5	131	1.9
Cerro Tololo Inter-American Observatory	4-m	2.7/8/15	298	2.6/2.7
	1.5-m	7.5/13.5/30	332	1.4/2.4
	1.0-m	10	223	0.9/2.1
	0.9-m	13.5	307	1.6/1.0
	0.6/0.9-m Schmidt	3.5	191	1.3

Table 1 lists the NOAO telescopes. At both sites, the premier 4-meter telescopes are moderately wide-field (45 arc minutes) Ritchey-Chrètien reflectors. At Kitt Peak, an f/15 secondary is used to optimize infrared capabilities and achieve commonality with the 2.1- and 1.3-meter telescopes. The new 3.5- meter WIYN telescope on Kitt Peak will provide wide fields, up to 1 degree for the multiobject spectrometry port and 0.5 degree for the WIYN port. The WIYN telescope has already delivered images at the 0.4'' level. The Schmidt telescopes at KPNO and Cerro Tololo Inter-American Observatory (CTIO) are university-owned, with the observing time shared. They are both capable of 5-degree fields (but limited at the moment to 1 degree at KPNO with a 2048 x 2048 charge-coupled device (CCD) and at CTIO to less than that with a 1024 x 1024 CCD). At CTIO the 1.0-meter telescope is shared with Yale University and the 0.6-meter telescope (dedicated to single-channel photometry) is shared with Lowell Observatory. All the telescopes with apertures of 1 meter or less have very restricted instrumentation to provide for efficient operation.

KPNO hosts approximately 600 astronomer-visits per year for use of its telescopes and CTIO approximately 200 per year. Table 1 lists the scheduling and oversubscription rates (nights requested/nights scheduled) in 1994 for all NOAO telescopes. It shows that in 1994 the smaller (2.1 m or less) telescopes at KPNO provided some 1200 observer-nights, or approximately 43% of all NOAO observing time.

Helmut Abt's studies* on the cost-effectiveness of telescopes, the research done at NOAO, and institutional productivities all show that NOAO has been scientifically productive. Moreover, many major astronomical discoveries have been made with NOAO telescopes. A few of the many examples include the Infrared Tully-Fisher relationship, the Bootes Void, the Lyman alpha forest, the first gravitational lens, and the flat rotation curves of spiral galaxies.

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*Abt, H. 1990. Publ. Astron. Soc. Pacific 92, 249 (1980); 97, 1050 (1985); 105, 794 (1993).

Figure 4a. The 1993 NOAO funding distribution (in $M; total is $27.1M).

The competitive access to NOAO telescopes is crucial to the nation's science. The panel examined NSF grant funding over the three-year period from 1991 to 1993 to identify the dollar amounts that have gone to researchers at institutions with guaranteed access to telescopes with apertures of 2 meters and larger, and those at institutions lacking such facilities. Omitting astrometric programs and solar astronomy, 55% of the funding in OIR observational research has gone to those with "perennial access." The remaining 45% has gone to those with "annual competitive access," and who presumably rely absolutely on NOAO for the capability to carry out some, most, or even all of their research. Since NOAO now includes only 20% of the telescopes with apertures of 2 meters or greater, the "annual" category is extremely competitive scientifically, and NOAO has played a fundamental role in enabling these scientists and their graduate students to conduct their research.

Figure 4 shows more detailed breakdowns of the NOAO budget in 1993, the most recent year for which such data are available. Figure 4a represents funding explicitly designated for support of Kitt Peak National Observatory (KPNO); Cerro Tololo Inter-American Observatory (CTIO); the U.S. Gemini Project Office (USGPO); general administrative, scientific, and technical support at the NOAO Tucson headquarters ("central") and the Association of Universities for Research in Astronomy, Inc. (AURA), management fee (yellow); and support of solar astronomy (green) through the National Solar Observatory at Sacramento Peak (NSO/SP) and Tucson (NSO/T) and the Global Oscillation Network Group (GONG). Figure 4b shows the distribution that results when the Tucson central services and AURA management are prorated among the various functions they support, according to estimates provided by NOAO. In Figure 4b, the support of the image reduction and analysis facility (IRAF) project, the USGPO, and the WIYN telescope are shown separately. The chart shows that of the $27.1 M NOAO budget for 1993, $18.6 M was devoted to support of nighttime OIR astronomy and $8.5 M was devoted to solar astronomy.

Currently, NOAO has a net staff of 455 full-time equivalents (FTEs), of which 224 are located in the downtown Tucson headquarters, 48 are located at Kitt Peak, 41 at Sacramento Peak, and 142 at Cerro Tololo. Figure 5 shows the organizational distribution of the NOAO staff. Figure 6 shows the distribution of the CTIO staff according to function, and Figure 7 shows the same distribution of the KPNO and NOAO Tucson staff, excluding NSO and GONG. The net NOAO staffing devoted to nighttime OIR astronomy has decreased by about 6% from 1989 to 1994.

Figure 5. Distribution of NOAO staff by organization.

Figure 6. Distribution of CTIO staff according to function.

To understand the diversity of OIR facilities in the United States, it is important to consider the historical context in which the national observatories were established. In the early 1950s, the California astronomers had a monopoly on facilities at excellent sites, with the telescopes on Mt. Wilson, Mt. Palomar, and Mt. Hamilton. To enable scientists from other institutions to carry out front-line research in OIR astronomy, KPNO was founded in 1957 by a consortium of universities that established AURA to manage the operations for the NSF. CTIO was founded by NSF and AURA in 1964 to provide access to Southern Hemisphere skies. Since that time, most of the original signatories have built their own Northern Hemisphere telescopes and so are much less dependent on KPNO. In the meantime, departments of astronomy have grown in many universities that were not original signatories to the AURA agreement and that today do not have access to independent observatories. Approximately 50% of active OIR astronomers in the United States have access to independent observatories, while the remaining 50% must rely on NOAO for access to telescopes.

Figure 7. Distribution of KPNO plus NOAO Tucson staff according to function (excluding NSO and GONG).

Table 2 lists all current and planned telescopes with aperture greater than 2.0 meters that will be available to U.S. astronomers, including both the "national" telescopes operated by NOAO and NASA and those telescopes operated by independent observatories (including the Smithsonian Astrophysical Observatory). It shows that the telescopes at the independent observatories currently comprise roughly 81% of the total collecting area (and 76% of the net diameter) of such telescopes and that this situation will prevail for the foreseeable future. Even more remarkable is the fact that the net area of all major U.S. telescopes will increase by a factor of 2.45 within a decade. The net capital investment (not including operating expenses) of private and state funds in telescopes that will be built by the independent observatories between 1985 and 2000 already exceeds $250 M and will certainly exceed $300 M before the end of the century.

Table 2. Current and Planned U.S. Telescopes with Aperture Greater Than 2.0 Meters

	Public Observatories			Independent Observatories
	Telescope	Aperture (m)	Area (m^2)	Telescope	Aperture (m)	Area (m^2)
CURRENT	KPNO	4.0	12.6	Keck 1	10	78.5
	CTIO	4.0	12.6	Palomar	5	19.6
	0.4 x WIYN	3.5	9.6	MMT	4.5	15.9
	KPNO	2.1	3.5	ARC	3.5	9.6
	0.9 x IRTF	3.0	7.1	0.6 x WIYN	9.6	3.5
				Lick	3	7.1
				Texas	2.7	5.7
				Dupont	2.5	4.9
				MDM	2.5	4.9
				WIRO	2.4	4.5
				Steward	2.3	4.2
				Hawaii	2.2	3.8
				Texas	2.1	3.5
	SUBTOTAL*	14.2	38.9		44.8	167.8
		24%	19%		76%	81%
PLANNED	0.45 x Gemini N	0.45 x 8	50.3	0.9 x Keck2	10	78.5
	0.45 x Gemini S	0.45 x 8	50.3	0.5 x LBT	2 x 8.5	113.4
	1/3 x Keck 1	1/3 x 10	78.5	0.5 x HET	~ 8	35.2
				Magellan I	6.5	33.2
				Magellan II	6.5	33.2
				MMT Upgrade	6.5	33.2
				SDSS	2.5	4.9
	SUBTOTAL*	10.5	71.4		42.8	248.7
		20%	22%		80%	78%
	TOTAL*	24.7	110.3		83.0	400.7
		23%	22%		77%	78%

*The actual telescope apertures or areas are listed, but these values are multiplied by the fractions of time allocated to U.S. astronomers to calculate the subtotals and totals. The sums in the independent observatories column do not include the University of Hawaii shares of international telescopes on Mauna Kea, such as Gemini North, the CFHT, the United Kingdom Infrared Telescope, and the Subaru Telescope. The MMT upgrade replaces the MMT, whose contribution has been subtracted from the total.

Key to Table 2:

ARC: Located at Apache Point Observatory, New Mexico, and operated by the Astrophysics Research Corporation, a consortium of the University of Chicago, New Mexico State University, Princeton University, the University of Washington, and Washington State University.

CFHT: Canada-France-Hawaii Telescope.

Dupont: Located at Las Campanas Observatory, Chile, and operated by the Carnegie Observatories.

Gemini N: (See Plate 1.) Located on Mauna Kea and operated by the IGP. Time allocation: U.S. national access--45%; international partners--45%; University of Hawaii--10%.

Gemini S: Located on Cerro Pachon, Chile, and operated by the IGP.

Hawaii: The University of Hawaii Telescope.

HET: Hobby-Eberly Telescope, located at MacDonald Observatory, Texas; a collaboration between the University of Texas, Pennsylvania State University, Stanford University, the University of Munich, and the University of G^ttingen.

IRTF: The Infrared Telescope Facility located on Mauna Kea and operated by NASA Planetary Sciences Division.

Keck 1: (See Plate 2.) Located on Mauna Kea and operated by CARA, a consortium of the California Institute of Technology and the University of California system.

Keck 2: Twin of the Keck 1 telescope under construction on Mauna Kea. Funded partially by NASA Planetary Sciences Division, which will provide national access to 1/6 of the telescope time of both Keck 1 and Keck 2. The remaining time will be under the control of the California Institute of Technology and the University of California system.

LBT: Large Binocular Telescope, located on Mt. Graham, Arizona; a collaboration between the Steward Observatory, University of Arizona; Arcetri Observatory, Florence, Italy; and Research Corporation, a U.S. foundation for the advancement of science.

Lick: Shane Telescope, located on Mt. Hamilton, California, and operated by the Lick Observatory, University of California.

Magellan I: Located at Las Campanas Observatory, Chile; a collaboration between the Carnegie Observatories and the University of Arizona.

Magellan II: Twin to Magellan I telescope.

MDM: Located on Kitt Peak and operated by the University of Michigan, Dartmouth University, and the Massachusetts Institute of Technology.

MMT: Multiple Mirror Telescope, located on Mt. Hopkins, Arizona, and operated jointly by the University of Arizona and the Smithsonian Astrophysical Observatory. To be upgraded to a single-mirror telescope and renamed the Monolithic Mirror Telescope.

Palomar: Located on Mt. Palomar, California, and operated by the California Institute of Technology in partnership with the Carnegie Observatories and Cornell University.

SDSS: Sloan Digital Sky Survey, located at Apache Point Observatory, New Mexico, and operated by a consortium including the University of Chicago, Fermilab, the Institute for Advanced Study, Johns Hopkins University, Princeton University, the University of Washington, the U.S. Naval Observatory, and a number of astronomical institutions in Japan.

Steward: Located on Kitt Peak and operated by the Steward Observatory, University of Arizona.

Texas: Operated by MacDonald Observatory, University of Texas.

WIRO: Wyoming Infrared Observatory, operated by the University of Wyoming.

WIYN: Located on Kitt Peak and operated jointly by the University of Wisconsin, Indiana University, Yale University, and NOAO. Forty percent of the observing time is available for national access via NOAO, and 60% remains in the control of the participating universities.

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