Opportunities for Coordination between Organizations and for Cooperation with Industrial and International Partners
The international exoplanet research landscape is very vibrant, as amply demonstrated by very successful past collaborations. Excellent future collaboration opportunities include utilization of existing and future instrumentation and technology development. For example, very successful collaborations between NASA and the European Space Agency, as well as the space agencies of individual countries, exist for many of the largest astrophysical facilities, including the Hubble Space Telescope and the James Webb Space Telescope. As another example, Europe has played an important role in the exploitation of the Kepler and K2 mission data using ground-based telescopes.
Similarly, collaborations between industrial partners and government agencies have proven essential in enabling several missions. Several industrial partners have also been actively involved in NASA’s four large mission concept studies for the next decadal survey.
In the light of the first recommendation of this committee for NASA to lead a direct imaging mission capable of measuring the reflected-light spectra of temperate terrestrial planets orbiting Sun-like stars, and the undoubtedly significant cost, long lead time, and technical complexity of such a project, collaboration with foreign space agencies and associated exoplanet scientists and engineers is a logical path, and may be a necessary path. From a scientific point of view, there is already great enthusiasm in both Europe and Asia to potentially participate in such a mission.
Ground-based instrumentation is a strong point of European astronomy, and exoplanet science in particular. Just as with Kepler and K2, the NASA Transiting Exoplanet Survey Satellite mission will strongly benefit from the supporting radial velocity follow-up observations with the dedicated radial velocity machines such as High Accuracy Radial Velocity Planet Searcher (HARPS), HARPS-N (and HARPS-3, under development), Calar Alto High-Resolution Search for M Dwarfs with Exoearths with Near-Infrared and Optical Échelle Spectrographs, Fiber-Fed Échelle Spectrograph, and the recently commissioned Échelle Spectrograph for Rocky Exoplanet- and Stable Spectroscopic Observations. In fact, the committee stresses here that coordination between all the different parties, in conjunction with the national radial velocity machinery, is key to avoid unnecessary duplication and consumption of valuable resources.
As the committee recommends that the National Science Foundation invest in both the Giant Magellan Telescope (GMT) and Thirty Meter Telescope (TMT) and their exoplanet instrumentation, it also notes that important synergies in technology development with the European Extremely Large Telescope (ELT) are likely and will be beneficial. The ELT is fully funded and under construction, and the first-light instrument Mid-Infrared E-ELT Imager and Spectrograph, a mid-infrared high-dispersion Integral Field Unit spectrograph and imager, is
specifically designed for characterization of thermal emission of exoplanets. One of the great promises of giant segmented mirror telescope (GSMT) science is probing molecular oxygen in the transmission and reflected-light spectra of temperate terrestrial planets, requiring optical high-dispersion spectroscopy, and in the case of reflected-light studies in combination with high-contrast imaging. For all telescope projects, such instrumentation still has a long lead time, needing significant technology development (such as making extreme adaptive optics work in the optical). Therefore, it would strongly benefit from development of optimized coronagraphs coupled to high-dispersion spectrographs, and would strongly benefit from open sharing of technology and ideas, with the aim to significantly expedite their deployment on the GSMTs.
Private foundations have become increasingly active in supporting exoplanet and related science since the last decadal survey. Examples include the Breakthrough Initiative, which funds a number of efforts centered on the search for extraterrestrial intelligence, the 51 Pegasi b Postdoctoral Fellowship funded by the Heising-Simons Foundation, and the astrobiology-focused Collaboration on the Origins of Life funded by the Simons Foundation. Currently, these initiatives mostly set their own agendas without coordinating with each other or national bodies, which has both advantages and disadvantages. The advantages are that private foundations can be nimble and respond quickly to emerging opportunities and also fund riskier projects that require preliminary data to demonstrate their efficacy. On the other hand, the lack of coordination can lead to duplication of effort or the support of projects that do not advance the field’s primary strategic objectives. Better communication between foundations and government agencies, and the consideration by private foundations of the strategic plan in this report and in the National Academies of Sciences Astrophysics and Planetary Science decadal survey reports, would reduce the disadvantages of private funding while maintaining most of the advantages.
The GMT and TMT projects have also enjoyed substantial private investment, both directly from philanthropic individuals and foundations and through the participation of private universities. This investment has helped advance the design of the telescopes and instruments and also retire key risks (e.g., the casting and polishing of the off-axis mirrors for the GMT primary). Nevertheless, it is clear that private funding alone cannot bring these projects to fruition. U.S. federal funding is essential for these projects to succeed and, as described elsewhere in this report, the exoplanet science that they would enable is exceptionally compelling. Thus, the recent collaboration of the GMT and TMT organizations with the NSF (through the National Optical Astronomy Observatory) to articulate a community-based science program for presentation to the next decadal survey is a welcome development. Continuation of this public/private partnership is perhaps the best chance for realizing the ambitious program of ground-based exoplanet science outlined in this report.
As is evidenced by many of the recommendations in this report, as fields of study mature, the scope of the scientific questions that are being addressed increases, and the complexity and cost of instruments, telescopes, and missions continue to correspondingly increase. At some point, these endeavors become too large to be affordable, built, and maintained by any single agency, university, company, or even country. One obvious example of this is in the field of particle physics with the Large Hadron Collider, a project undertaken by a large collaboration of scientists, universities, and countries. The field of exoplanets has now reached the maturity and ambition that answering some its most profound questions—notably, “Does life exist on planets orbiting other stars?”—requires projects that are likely too large to be realistically accomplished by any single entity. Nevertheless, there are often institutional barriers to forming partnerships between various agencies or organizations, which slow the pace of the field and hinder the progress of the scientific community in advancing its knowledge of these big questions.
Finding: By continuing to find novel ways of partnering with each other, and by removing or reducing institutional barriers to such partnerships, agencies may be able to better address some of the most profound scientific questions outlined in this study, which often require instruments, telescopes, or missions that are too ambitious or expensive for any individual agency to fund, build, and operate alone.