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Pathways to Discovery in Astronomy and Astrophysics for the 2020s (2023)

Chapter: 5 Evaluating and Balancing the Operational Portfolio

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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
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5

Evaluating and Balancing the Operational Portfolio

Whereas Chapter 4 describes the research infrastructure, this chapter focuses on the suite of currently operating telescopes and missions that drives the scientific advances of today. Fully capitalizing on this suite of facilities requires managing and balancing the resources required to operate and maintain them, and upgrading capabilities where needed, in a way that returns maximum scientific benefit. This chapter draws from all of the program panel reports in the appendices, and in particular from the Enabling Foundation for Research panel report (see Appendix H).

Although the largest component of national investment in astronomy goes to the development and construction of future major observatories and facilities (Chapter 7), today, the currently operating facilities on the ground and in space are the primary tools for collecting data that drive scientific discovery and progress in astronomy and astrophysics. Support for publicly shared facilities comprises the largest fraction of the National Science Foundation (NSF) Division of Astronomical Sciences (AST) annual budget,1 and a large share of the National Aeronautics and Space Administration (NASA) Astrophysics Division budget that is not devoted to mission development. It is this funding that keeps observatories such as the Hubble Space Telescope, Chandra, Fermi, the Transiting Exoplanet Survey Satellite (TESS), the Neil Gehrels Swift Observatory, the Nuclear Spectroscopic Telescope Array (NuSTAR), the Atacama Large Millimeter/submillimeter Array (ALMA) (the U.S. share), the Karl G. Jansky Very Large Array (VLA), and the Gemini Observatories, among others, running and delivering cutting-edge science. Collectively, such facilities have been extraordinarily productive (see Chapter 2) and cost effective in seeding a steady stream of major scientific discoveries using panchromatic capabilities that are central to their advancing broad decadal scientific priorities.

The vitality of these facilities is routinely assessed, with NASA and NSF engaging in periodic reviews of their portfolios of operating missions and facilities. The importance of evaluating the operational mission/facility portfolios on a regular basis was underscored by the 2000 and 2010 astronomy and astrophysics decadal surveys, and for NASA in a 2016 National Academies study of NASA mission extensions and the

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1 National Science Foundation, 2020, FY2021 Budget Request to Congress, https://www.nsf.gov/about/budget/fy2021/pdf/fy2021budget.pdf.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

senior review process.2 All of these studies emphasized the importance of such reviews to optimize the scientific return on these facilities’ investments.

As with the assessment of the research foundation activities in Chapter 4, the main interest of this survey is not with the details of these stewardship processes, but rather with assessing at a high-level which aspects of the processes are functioning effectively and which are less healthy, owing to factors such as growing programmatic imbalances, unforeseen events, or rapid changes in the overall scientific landscape or priorities since the last decadal survey. As part of this assessment, the committee considered not only the processes for prioritizing individual missions and facilities within the agency portfolios but also the overall balances of investment between facilities and the many other types of investments that are also needed to advance science.

Before addressing NSF and NASA portfolios individually, it is worth highlighting general areas in which this committee believes that the current management of operating facilities has been particularly successful. The NASA Astrophysics Senior Review of Operating Missions has proven to be especially effective in setting funding priorities for operating missions (post-prime mission), and for establishing criteria and a decision process for terminating missions. Its 3-year cadence ensures that all projects regularly document their scientific productivity, user demand, data products, operational plans, and budget allocations on a regular basis. In contrast, the NSF Senior and Portfolio Reviews are conducted less frequently and without a predictable cadence (last conducted in 2006 and 2011–2012).

This committee did, however, identify areas of concern, where imbalances or inconsistencies across the agency portfolios now pose threats to the overall science return, vitality, and sustainability of the astronomy and astrophysics programs. For NSF, the chief concern is insufficient funding to support operations of high-impact scientific facilities that are at the core of astronomy’s current and future ground-based research enterprise. The result, as detailed in Chapter 4, is a trend toward a declining fraction of the AST budget for other purposes, most notably the Astronomy and Astrophysics Research Grants (AAG) program. The problem is poised to become much worse with the imminent commissioning of the Rubin Observatory and the Daniel K. Inouye Solar Telescope (DKIST) observatories and is an existential concern when contemplating the exciting set of proposed Major Research Equipment and Facility Construction (MREFC) projects (the U.S. extremely large telescope program, the Next Generation Very Large Array (ngVLA), the ground-based Cosmic Microwave Background Stage 4 [CMB-S4] experiment), and the sustaining instrumentation program recommended by this survey (see Chapter 7). For NASA, a serious concern is the exclusion of a major facility (the Stratospheric Observatory for Infrared Astronomy [SOFIA]) from the Senior Review process. This committee addresses these and a few other, less serious, concerns separately for each agency.

5.1 NSF OPERATIONAL FACILITIES

This section provides an analysis of and recommendations related to NSF’s current model for the operation of major facilities, along with assessments and recommendations on maintaining its current portfolio, especially in the optical and infrared (OIR).

5.1.1 NSF Funding for Major Research Facilities

In contrast to budgeting for NASA space missions, which include end-to-end funding for construction, launch, and operations through the prime mission phase, the NSF budgets instead separate the funding

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2 National Academies of Sciences, Engineering, and Medicine, 2016, Extending Science: NASA’s Space Science Mission Extensions and the Senior Review Process, The National Academies Press, Washington, DC.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
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streams for facility construction and operations. Under current NSF regulations, the construction of projects that cost more than $70 million may be funded by the agency-wide MREFC program. Proposals to the program are based on design and development efforts funded by a division and/or directorate, and, if the proposals are accepted, the MREFC program takes over and provides processes for planning, oversight, and review throughout the construction process. This structure is ideal for astronomy, with its reliance on transformative, widely shared facilities.

However, while the MREFC process has supported building revolutionary facilities like ALMA and Rubin Observatory, the program does not provide support beyond construction, leaving the operations and maintenance (O&M) costs of these facilities as the responsibility of the sponsoring directorate, but without a commensurate, sufficient increase in the directorate’s funding line to account for operations costs. With many NSF facilities having lifetimes of 50+ years, and annual operations costs typically amounting to 4–7 percent of the original construction cost,3 the total lifetime cost of O&M can easily rival or exceed the original cost of construction. Moreover, the O&M costs are typically not carried by the directorate as a whole; instead they are passed down to an individual division. For astronomy facilities, these costs are almost always borne by AST, with occasional contributions from Physics or Polar Programs. The division must then carry these costs for the remainder of the productive scientific lifetime of the observatory.

Research communities from across NSF’s divisions have expressed mounting concern about the impact of the “O&M mortgage” on the overall health of their fields. In response, the U.S. Senate Committee on Appropriations issued guidance to the National Science Board (NSB) in its FY 2017 appropriations bill for the Departments of Commerce, Justice, Science and Related Agencies (S.2837):

Operations and Maintenance Costs—The Committee is concerned that operations and maintenance costs for NSF-funded research facilities require an increasingly large percentage of the funding for Research and Related Activities, especially in a budget environment where overall domestic spending is restrained and annual operations and maintenance costs increase faster than overall NSF spending. The Board is directed to consider whether this issue merits a change in NSF’s funding principles or budgetary formulation processes, including considering the research infrastructure funding approaches within other Federal agencies, and whether a separate operations account is merited.

The NSB responded to this charge with a 2018 report (NSB-2018-17) titled Study of Operations and Maintenance Costs for NSF Facilities. This report found that in nearly all facilities-heavy divisions and directorates, including AST, O&M spending has increased faster than division and directorate budgets. Figure 5.1 shows the fraction of the division budgets represented by O&M costs for several different divisions. The report notes that in divisions other than AST (Physics, Materials Research, Earth Sciences, Geosciences, Ocean Sciences, Earth Sciences), this fraction has leveled off at below or around 30 percent. AST stands out among all other divisions as having facility O&M costs that are projected to continue to rise.

The two divisions with the highest O&M budget fractions are AST and Oceanography (OCE), and this is no coincidence. Both fields rely heavily on shared national research facilities—in the case of AST, mainly radio, submillimeter, and optical-infrared ground-based observatories, and for OCE, large oceanographic vessels. This research infrastructure model contrasts sharply with other divisions, such as physics, chemistry, materials science, and so on, where the bulk of research facilities reside within individual university and institutionally based laboratories.

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3 B. Goodrich, C. Dumas, M. Dickinson, R. Bernstein, and P. McCarthy, 2019, “Observatory Operating Costs and Their Relation to Capital Costs,” white paper submitted to Astro2020: Decadal Survey on Astronomy and Astrophysics, https://ui.adsabs.harvard.edu/abs/2019BAAS...51g.225G.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
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FIGURE 5.1 Percentage of selected MPS division budgets to facilities (O&M) and overall MPS share. Budget numbers through 2017 are actuals. Budget numbers from 2018 on are projections. The projected fraction for AST has been roughly consistent with this analysis up to the present date. NOTE: AST: Division of Astronomical Sciences; PHY: Division of Physics; MPS: Directorate of Mathematical and Physical Sciences; DMR: Division of Materials Research. SOURCE: National Science Board, 2018, Study of Operations and Maintenance Costs for NSF Facilities, NSB-2018-17, Alexandria, VA: National Science Foundation, May 24.

The main components of the current AST O&M portfolio are the National Radio Astronomy Observatory (NRAO) (including the U.S. share of ALMA and the VLA), the National Optical-Infrared Astronomy Research Laboratory (NOIRLab) (including the two Gemini telescopes, Kitt Peak National Observatory [KPNO], Cerro Tololo Inter-American Observatory [CTIO], and Datalab), the National Solar Observatory (NSO), Green Bank Observatory (GBO), Arecibo (see Section 5.1.5), and some elements of the AST Mid-Scale Innovations Program (MSIP; discussed separately in section 6.3.2). These facilities are all highly valued by the community, but their aggregate O&M needs have imposed a severe squeeze on the rest of the AST budget. Programs particularly impacted are the AAG individual grants line (see Section 4.2.1), support for technology through Advanced Technologies and Instrumentation (ATI) (see Section 6.1.2), instrumentation, and graduate education.

Soon, two new major MREFC facilities recommended by the Astronomy and Astrophysics in the New Millennium (Astro2000)4 and New Worlds, New Horizons in Astronomy and Astrophysics (Astro2010)5 decadal surveys, DKIST and the Vera Rubin Observatory, respectively, will place even greater strain on the AST budget. As stated in the 2018 NSB study:

The Division of Astronomy (AST): The Division of Astronomical Sciences situation is highlighted on p. 21-22 of the NSB report, which notes: “[W]ith limited budget growth, the almost $100 million in steady-state O&M

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4 National Research Council, 2001, Astronomy and Astrophysics in the New Millennium, The National Academies Press, Washington, DC.

5 National Research Council, 2010, New Worlds, New Horizons in Astronomy and Astrophysics, The National Academies Press, Washington, DC.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

needed when three state-of-the-art facilities that were, or will be, completed between 2012 and 2023 is challenging the division’s ability to manage its portfolio of existing and future facilities without severely affecting its investigator research program.”

The NSF AST has long been aware of the problem, and has attempted to adjust in response to rising facilities costs. AST undertook a portfolio review in 2011–2012, which was charged with examining how the program recommended by Astro2010 could be realized within a more limited budget profile than anticipated. The portfolio review recommended a course of divestment from a number of facilities. Some of these divestment recommendations were adopted, and provided a total cost savings of about $15 million per year. More extensive divestment of legacy, but scientifically productive, facilities, could generate an additional savings at this scale but are insufficient to compensate for the needs of upcoming facilities and at the same time fund individual investigator grants at a healthy level. As stated in the midterm assessment of the Astro2010 decadal survey, “divestment alone will not resolve the budget stresses imposed by rising facilities costs.”6 The midterm assessment report appealed to NSF and NSB to “consider actions that would preserve the ability of the astronomical community to fully exploit the foundation’s capital investments in ALMA, DKIST, [Vera C. Rubin Observatory, formerly known as the Large Synoptic Survey Telescope] LSST, and other facilities. Without such action, the community will be unable to do so because at current budget levels the anticipated facilities operations costs are not consistent with the program balance that ensures scientific productivity.”7

As this committee assessed the ambitious set of proposed MREFC projects for the coming decade, it became clear that to implement any of them, and at the same time support continuation of the world-leading observatories such as Rubin, DKIST, ALMA, the VLA, and Gemini, requires a fundamental change in the budgets available for AST O&M. The major projects presented to this survey carry capital costs to the MREFC line ranging from hundreds of millions of dollars to approximately $2.5 billion, with corresponding operating costs, ranging from $20 million to $100 million per year (for any one facility, as estimated by the projects themselves). When compared to the approximately $80 million currently available in the AST budget outside the O&M line, the current challenge has the real potential to escalate the existing funding problem in the AAG program (Chapter 3) into a full crisis in the near future, when DKIST and Rubin Observatory are fully operational. Although some of the pressure will be relieved by planned phased retirements of current facilities (e.g., retirement of the VLA when the ngVLA comes into operation), it will not by itself relieve the existential threat to the sustainability of the NSF astronomy budget.

In short, the structural difficulty of funding ongoing operations of long-lived, scientifically productive astronomy facilities places a profound challenge in front of the roadmap laid out by this decadal survey. The same transformative projects that could readily attract MREFC funding would simultaneously make it impossible to actually carry out the science because of the inevitable underfunding of research grants to use the new facilities and because of the theoretical studies and computational tools needed to harness and interpret the data. Advancing astronomy and astrophysics takes cutting-edge facilities, the means to analyze and interpret the data, and also the theory and open-ended ideas that will make the leaps from data to discoveries.

The only ways out of this dilemma are through augmentations to AST’s overall budget or through changes to the current NSF model for funding of construction and operations of large facilities. It is imperative that the agency work with the AST division and MPS directorate to develop a sustainable budget and/or model for construction and operation of new facilities, one that allows our community to maintain an appropriate balance of investments in all of the other critical elements of the enabling foundation for research that have been outlined in Chapter 4.

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6 National Academies of Sciences, Engineering, and Medicine, 2016, New Worlds, New Horizons: A Midterm Assessment, The National Academies Press, Washington, DC.

7 Ibid.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

The 2018 NSB report makes several recommendations aimed at achieving this objective. One key recommendation is stronger agency-level oversight and involvement in strategic planning for major facilities. A longer time scale for budgetary planning (currently, facility budgets contain 5-year projections) is also suggested. Notably, the report discusses a vision for a more flexible implementation of the MREFC account, under which partial funding for O&M for a new facility could be allocated from MREFC for a limited period (5–10 years). O&M costs could then be gradually absorbed into a division or directorate budget. This welcome adjustment could help to solve the problem of operations costs for shorter-lived facilities; it would only temporarily alleviate but not eliminate the funding pressures from Astronomy’s existing capital investments. Other solutions, such as creating an operations budget line at the MPS or AST levels sized to accommodate O&M for current facilities, the planned profile of which would anticipate future needs, would also address this issue.

Conclusion: The current pressure imposed by operations costs of large NSF facilities on the grants and other NSF programs will escalate to unsustainable levels by mid-decade unless changes are made to the way that large facilities are supported.

Recommendation: The National Science Foundation (NSF) should develop a sustainable plan for supporting the operations and maintenance costs of its astronomical facilities, while preserving an appropriate balance with funding essential scientific foundations and the remainder of the NSF Division of Astronomical Sciences portfolio. The addition of new MREFC facilities should be contingent on implementation of this plan.

5.1.2 Managing the NSF Facilities Portfolio

As highlighted earlier, periodic reviews by NASA and NSF of their portfolios have proven to be effective mechanisms for maximizing science return and prioritizing budgets. The NASA Senior Review, which is undertaken every 3 years, has proven to be an extremely effective way to maintain high scientific productivity while managing costs. In response to a recommendation in the Astro2010 decadal survey, NSF organized a portfolio review of its operating facilities in 2011–2012, but none since. Reviews on a regular cadence allow for a periodic evaluation of the productivity and science return from facilities and can help to identify where efficiencies can be realized or where funding augmentations might be required to capitalize on new scientific opportunities. Such reviews can also identify those observatories from which NSF might divest and subsequently decommission. These goals largely mirror those carried out in the 2011–2012 portfolio review, and this is a practice worth implementing on a regular basis to ensure that NSF facilities regularly assess, document, and justify their performance and service to science and education.

Similar to the NASA Senior Review process, NSF facility reviews would focus on scientific promise, productivity, and budgetary efficiency. The committee appreciates that some aspects of facility reviews have taken place as parts of the review of operating agreements for observatories, but such reviews are not an appropriate substitute for a review that considers the entire portfolio simultaneously on a holistic basis. The cadence of NSF reviews needs to be sufficiently frequent to allow facilities to respond to changes in the scientific and budgetary landscape in advance of the decadal and mid-decadal processes (i.e., at least twice a decade), but not so frequent that the facilities do not have time to implement and evaluate changes made in response to a previous review (i.e., not as frequent as every 2 years).

Recommendation: The National Science Foundation Division of Astronomical Sciences should establish a regular cadence of reviews of its operational portfolio, at a frequency that is sufficient to respond to changes in scientific and strategic priorities in the field. An appropriate target is at least two reviews per decade.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

5.1.3 Investment in Mid- and Small-Scale Ground Facilities

Over the past decade, the system of ground-based telescopes in the United States has evolved significantly, in both the radio and OIR parts of the electromagnetic spectrum. Radio astronomy has had federal funding support for the construction and operation of ALMA, an upgrade to the VLA, and a collection of smaller specialized telescopes, collaborations, and instrumentation, albeit at the expense of the closing of the Combined Array for Research in Millimeter-wave Astronomy (CARMA) and the elimination of the University Radio Observatories program at NSF. In the OIR, key developments include the construction of the national flagship telescopes DKIST and Rubin Observatory, the innovative repurposing of several smaller ground-based telescopes (e.g., the Dark Energy Camera [DECam], the Dark Energy Spectroscopic Instrument [DESI], and the Zwicky Transient Facility [ZTF]). Despite the investments in cutting-edge smaller facilities and experiments, capable radio and OIR observatories are currently aging, and with insufficient investment are quickly becoming less competitive on the world stage, even among some of the largest U.S. facilities.

The operating ground OIR and radio facilities play vital roles, both in supporting observations with larger flagship facilities and in generating major discoveries on their own. They are fundamental to preserving a balanced portfolio of capabilities and investments in U.S. astronomy and astrophysics. Flexible and accessible ground-based telescopes can respond to a rapidly changing scientific environment through technology upgrades in cameras and detectors.

Critical to the future effectiveness of ground-based facilities are updates to instrumentation. Technology advances significantly over the decades-long lifetimes of these facilities, as do the needs of the scientific community. A robust investment in instrumentation upgrades can enable an observatory to maintain its competitiveness for far less than the cost of building a new observatory. The development of adaptive optics in the 1990s serves as an excellent case in point; it led to groundbreaking advances such as the direct imaging of exoplanets, and the precise definition of the orbits of stars that determined the gravitational force fields near the black hole at the center of the Milky Way, work recognized with the 2020 Nobel Prize in Physics. The upgrade of the receivers at the VLA led to a factor of 10 increase in sensitivity for continuum observations at the higher frequencies and nearly complete access to the 1–50 GHz frequency range.

NSF programs for supporting new and upgraded instrumentation are available at scales ranging from the MSIP and Mid-scale Research Infrastructure (MSRI) mid-scale opportunities down to the ATI program, which supports smaller projects (see Chapter 6). Over the past decade, these programs have supported a wide range of meritorious projects, including for example the Event Horizon Telescope, ZTF, and a number of CMB projects.

New and upgraded instrumentation on telescopes of all scales has also been supported significantly by private foundations and philanthropy. Investments by foundations such as Moore, Heising Simons, Sloan, Keck, Packard, and others have been crucial, often in partnership with federal funding to develop new, ambitious instruments, as well as repurposing smaller telescopes for targeted objectives. A few of many examples of these public-private instrumentation partnerships include the Las Cumbres Observatory, the ZTF, the PolarBear/Simons Array, the BICEP (Background Imaging of Cosmic Extragalactic Polarization) and Keck Array, the Keck Cosmic Reionization Mapper, and the Keck Planet Finder.

When assessing the current balance across these programs, the committee identified a notable gap in the support for instrumentation on OIR telescopes. Previously, some of this gap was filled by the Telescope System Instrumentation Program (TSIP), in which NSF provided money for development on private facilities in exchange for public observing time. During 2002–2011, NSF invested $33 million in 19 instrumentation projects for five observatories—Keck, the Multiple Mirror Telescope Observatory, Magellan, the WIYN (Wisconsin-Indiana-Yale-National Optical Astronomy Observatory [NOAO]) Observatory, and the Large Binocular Telescope—and providing in return 453 nights of public access observing time on seven telescopes (the Keck and Magellan Observatories each have two telescopes), which was allocated through the NOAO time-allocation process.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

However, TSIP was phased out early in the last decade and replaced by the MSIP program. Notably, unlike TSIP, MSIP does not require a return of public access in exchange for supporting instrumentation on private telescopes. A number of MSIP projects did provide public access time—for example, 40 Keck telescope nights over 4 years resulting from funding for the Keck Planet Finder, 60 public nights per year on the Center for High Resolution Astronomy (CHARA) array, 2,840 hours per year on the Las Cumbres Observatory global telescope network, and public-access targets of opportunity observations on ZTF, the latter two mainly for time-domain applications. Applications for time and the time-allocation processes are coordinated by NOIRLab through a common once-per-semester process. However, overall, since the replacement of TSIP with MSIP, the number of publicly available nights on leading facilities such as Keck and on capable 2–4 m class telescopes have decreased significantly.

Strategic use of ground-based telescopes has also proven to be advantageous for supporting the scientific goals of NASA space missions, and, as a result, NASA has now joined NSF as a major investor in ground-based OIR observatories and instrumentation. As a partner in the Keck Observatory, NASA allocates one-sixth of the time on the two 10 m telescopes (100 nights per year total) for public access.8 The NASA-NSF Exoplanet Exploration Program (NN-EXPLORE) has funded construction of exoplanet-focused instruments and made available telescope time on the WIYN (adding a powerful new Doppler spectrograph), the Anglo-Australian Observatory, the Small and Moderate Aperture Research Telescope System (SMARTS), and Miniature Exoplanet Radial Velocity Array-Australis (MINERVA-Australis) observatories. NASA also operates the 3 m Infrared Telescope Facility (IRTF) for astronomical and planetary-science observations. NASA funded construction of the Large Binocular Telescope Interferometer (LBTI), and in this case, 40 nights of public time were awarded for a single key project, the Hunt for Observable Signatures of Terrestrial Systems (HOSTS) survey, comprised of a nationally competed team of investigators.

The Department of Energy (DOE) is another significant contributor to U.S. ground OIR instrumentation, albeit focused on areas aligned with Office of Science objectives. In addition to providing the focal plane camera for Rubin Observatory, DOE has funded two extremely powerful optical survey instruments, DECam and DESI, using existing NOAO 4 m telescopes. DOE’s investments are motivated by the central importance of large-scale surveys for cosmology, and the instrument designs are in large part optimized for this purpose. However, the resulting data have wide astronomical utility.

These contributions from NSF, private foundations and philanthropy, NASA, and DOE have helped to maintain the vitality of the instrumentation on ground-based OIR telescopes but fall short of what is needed to maintain the competitiveness of the facilities. As one useful benchmark, the European Southern Observatory currently invests ~$10 million per year in instrumentation across its OIR telescopes, with another $15 million to $20 million invested by the partner organizations. Two major instruments on the Japan-led Subaru 8.4 m telescope, the Hyper Suprime-Cam and the future Prime Focus Spectrograph, have associated costs of $50 million and $86 million, respectively. Funding even shares of such instruments will require larger allocations than historically have been awarded through the TSIP or MSIP programs. The second challenge is the loss of public access time over the past decade, arising both from the discontinuation of the TSIP program and the effective withdrawal of the CTIO 4 m Blanco and KPNO 4 m Mayall telescopes from general public use during the course of the Dark Energy Survey and DESI (and their associated) multi-year surveys. The point is not to criticize whatsoever the decisions to undertake these important surveys, but rather to emphasize the ever-dwindling general public access to 3.5–10 m class OIR telescopes in recent years.

Although NSF’s MSRI program is an excellent new opportunity for funding larger ground-based astronomy instrumentation projects, it will be difficult to sustain the required level and cadence of new instrumentation through the program as currently planned. Given the significant investments, both public

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8 NASA Exoplanet Science Institute (NExScI), “Homepage,” California Institute of Technology, https://nexsci.caltech.edu.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

and private, in OIR telescopes, these facilities will remain a critical part of the U.S. ground-based astronomy program for decades and over time will need instrumentation upgrades to remain at the cutting edge. To achieve this, in Chapter 7, the committee recommends periodic, strategic calls through AST and NSF mid-scale program lines specifically to support upgrades of instrumentation on OIR facilities (private and public), both to maintain the scientific capabilities of those facilities and as a mechanism to expand community access to them. This includes a provision that such awards carry a requirement for allocating public observing time on the facilities, along the lines of the previously successful TSIP model, and for public release of data from the relevant instruments (after a suitable proprietary period). These mechanisms may not be suitable for some survey projects of experiments, but the broad objective or ensuring community benefit from the federal investments should be met to whatever extent possible.

Conclusion: U.S. competitiveness internationally in ground-based optical and infrared astronomy requires a stable funding mechanism for instrumentation development on existing ground-based telescopes that includes public access for the community.

5.1.4 Opportunities for Maximizing Public Investments

The U.S. system of ground-based astronomical observatories includes both federally funded facilities and facilities constructed and operated by academic and private institutions. In the radio, millimeter, and submillimeter, telescopes are typically federally funded, primarily by NSF AST. In the OIR, however, many of the most advanced and powerful ground-based observatories are funded and operated by consortia of academic institutions and private foundations. This funding model favors access by astronomers who are affiliated with the participating organizations that invest in the construction and support of those facilities. Another manifestation of this decentralized system is a lack of coordination across the many observatories, whether it be in terms of setting common priorities for new instruments, arranging for exchanges of observing time to limit duplication of instrumentation, or representing their common interests with the agencies.

The concept of a more coordinated system of ground-based observatories is hardly a new idea. On the recommendation of the Astro2000 decadal survey, NSF established the concept of the “OIR system,” which was intended to balance and optimize coordination of the national and private observatories. Ten years later, the Astro2010 report concluded that “Optimizing the long-term science return from the whole of the U.S. optical and infrared system requires a readjusting of the balance of the NSF-Astronomy program of support in three areas: (1) publicly operated national observatories; (2) private-public partnerships—such as support for instrumentation and upgrades of privately operated observatories …; and (3) investment in future facilities.”9 Following both reports, NSF organized strategic planning committees to develop decadal roadmaps for optimizing the OIR system, and these led to significant advances, not least the coordination of public access to privately run facilities as described earlier.

There is value in expanding this model beyond an ad hoc committee that issues a report once per decade toward a standing committee that would facilitate dialog between the diverse set of OIR stakeholder institutions and serve in the coordinating role envisaged above. The newly formed NOIRLab may be an entity that could convene (but not direct) such an activity.

Conclusion: As the cost of new instrumentation on ground-based OIR telescopes continues to increase, improved coordination and collaboration among facilities run and/or supported by private institutions,

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9 National Research Council, 2010, New Worlds, New Horizons in Astronomy and Astrophysics, The National Academies Press, Washington, DC, p. 177.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

universities, national laboratories, and private foundations could facilitate the development of a coherent national strategic plan for optical and infrared astronomy.

5.1.5 The Arecibo Observatory

In December 2020, the storied Arecibo radio telescope in Barrio Esperanza, Arecibo, Puerto Rico collapsed, ending a remarkably productive 55-plus year service to the astronomical, planetary, ionospheric, defense, and space-science communities. Innovative in design, its large, fixed dish with a suspended secondary enabled the discovery of over 500 pulsars, including the Hulse-Taylor binary pulsar that led to the discovery of gravitational radiation and the 1993 Nobel Prize in Physics. Other notable contributions include the first discovery of an exoplanet that was found orbiting the pulsar 1257+12; the Search for Extra-Terrestrial Intelligence (SETI); mapping of hydrogen gas emission over thousands of square degrees; understanding the composition of the ionosphere; the characterization of the properties and orbits of a number of potentially hazardous asteroids; radar mapping the surfaces of Mars, Venus, and Mercury (including its ice); and most recently probing fast radio bursts (FRBs) and intermittent pulsars to refine our understanding of the underlying physical mechanisms. At the same time, through its Ángel Ramos Foundation Visitor Center, it brought the wonders of the radio sky to many hundreds of thousands of students and non-specialists. Arecibo was also a focal point for education related to science, technology, engineering, and mathematics (STEM) in Puerto Rico, inspiring a young, diverse generation to pursue a career in science.

Arecibo opened a new, rich, view of the cosmos that over the years has helped to spark new ideas and more ambitious efforts. The results of its neutral hydrogen (HI) surveys of the Milky Way Galaxy and the census of the local HI content of nearby galaxies has motivated the larger efforts of the Square Kilometer Array and its precursors. Furthermore, the Five-hundred-meter Aperture Spherical Telescope (FAST) in Guizhou, China, builds on Arecibo’s 305 m diameter. Since first light in September 2016, FAST, which covers from 70 MHz to 3 GHz as compared to Arecibo’s 50 MHz to 10 GHz, has discovered over 200 new pulsars as of May 2021.10 For specific types of astronomical searches in much the same frequency range, other instrumentation approaches are better. For example, the Canadian Hydrogen Intensity Mapping Experiment (CHIME, 400–800 MHz) is just 80 m2, yet has greater mapping speed than FAST. The Hydrogen Intensity and Real-time Analysis eXperiment (HIRAX) will complement CHIME in South Africa. The Canadian Hydrogen Observatory and Radio-transient Detector (CHORD; 0.3–1.5 GHz, 512, 6 m dishes) and the proposed Deep Synoptic Array 2000 (DSA-2000) (0.7–2 GHz, 2000, 5 m dishes) are expected to discover, for example, many thousands of new pulsars and FRBs. This new generation of telescope blends modern high-speed digitization and correlation of multiple resolution elements with optimized hardware to simultaneously monitor large swaths of sky, acting like radio cameras. To complement these, in Chapter 7, the committee recommends commencing with the development of the ngVLA, an international effort to construct an array of more than two hundred 18 m telescopes operating from 1.2 to 116 GHz. While none of these new telescopes individually will replace all the capabilities of Arecibo, the combination of the radio cameras and ngVLA will be much more powerful for broadly advancing astrophysics in this frequency range.

The survey steering committee assessed the impact of Arecibo’s loss on the key science questions and program elements forwarded by the Astro2020 panels, while noting that these topics are largely outside the planetary and solar system science fields where Arecibo has had tremendous impact. When restricted to astrophysics alone, the most significant impact is the loss of the Arecibo’s contribution to discovering

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10 J.L. Han, C. Wang, P.F. Wang, T. Wang, D.J. Zhou, J.-H. Sun, Y. Yan et al., 2021, “The FAST Galactic Plane Pulsar Snapshot Survey: I. Project Design and Pulsar Discoveries,” Research in Astronomy and Astrophysics 21(5), https://iopscience.iop.org/article/10.1088/1674-4527/21/5/107/pdf.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

and timing pulsars that are elements of the Pulsar Timing Array (PTA). This set of pulsars is used to search for new sources of gravitational radiation. The PTA reveals gravitational waves with ~year periods through slight alterations in the arrival times of the emission from a catalog of millisecond pulsars. To date, over a quarter of these pulsars have been discovered with Arecibo and timed with telescopes including Arecibo, the Green Bank Telescope (GBT), and the VLA.

To reach the scientific goals of Astro2020, much of what was lost with Arecibo can be replaced, in the near term, by focusing more resources on timing with the VLA and GBT and by increased collaboration with the international community undertaking pulsar searches. As pointed out by the Panel on Radio, Millimeter and Submillimeter Observations from the Ground, the uniqueness of large single-dish telescopes like Arecibo, or very closely packed arrays, is their ability to search for new sources to improve the sensitivity of the PTA to gravitational waves. As noted above, the FAST telescope is already filling this role, and expanded international collaboration could ensure continued detection of relevant new sources. For pulsar timing, additional observing time will be needed on the GBT, and also the VLA, to provide the necessary phase-connected timing solutions. On few-year time scales, radio cameras will add search capabilities. This survey recommends commencing development of the ngVLA this decade and also recommends adding radio instruments as a strategic call at the mid-scale (Chapter 7). Therefore, in the longer term, new facilities will advance a broad range of Astro2020 science goals, including the detection and study of FRBs and pulsar timing.

Another important goal of Astro2020 is to enhance community engagement with astronomy. The Ángel Ramos Foundation Visitor Center has been a model for this. Chapter 3 addresses the importance of local community involvement in realizing the goals of Astro2020. In addition to this education and public outreach component, the observatory promotes demographic diversity in STEM through its impact on post-secondary education. These activities are important and worth continuing. Looking to the future, the reference design for the ngVLA calls for at least one of its antennas to be placed in Puerto Rico, an example of one path for Puerto Rican communities to become part of a connected network of telescopes that span from Hawaii to the Virgin Islands and that will at the same time be on the forefront of astronomical research and discovery.

Finding: There are future opportunities for continued utilization of the Arecibo site for radio astronomy, both through the ngVLA and mid-scale projects.

In summary, Astro2020 took a broad view of all the capabilities needed to ensure a strong future in radio astronomy. These recommendations are synergistic with the entire multi-messenger, multi-wavelength astronomy program. Even in the absence of Arecibo, and in light of multiple new ideas for its replacement (e.g, Roshi et al. 2021),11 our priorities for radio astronomy are the support of existing facilities; the phased buildup toward the ngVLA; and competed small- and mid-scale projects, all undertaken in an international context. Because of both its location and its communities, Puerto Rico has an important role to play in the future of radio astronomy, and it remains a good site for investing in mid-scale radio projects. The committee encourages NRAO/Associated Universities, Inc. and other entities to take advantage of this opportunity along the lines outlined in this report.

Conclusion: Much of the science relevant to the Astro2020 goals lost with Arecibo can be recovered through additional investment in existing facilities, and through international partnerships, while the new facilities recommended by this survey are realized.

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11 D.A. Roshi, N. Aponte, E. Araya, H. Arce, L.A. Baker, W. Baan, T.M. Becker et al., 2021, The Future of the Arecibo Observatory: The Next Generation Arecibo Telescope, white paper version 2.0, https://doi.org/10.48550/arXiv.2103.01367.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

5.2 NASA OPERATIONAL FACILITIES

NASA has a well-defined and effective process, the Astrophysics Senior Review of Operating Missions, proven to be effective in setting funding priorities and for establishing criteria and a decision process for terminating missions. The 2016 National Academies report Extending Science: NASA’s Space Science Mission Extensions and the Senior Review Process12 found that across all of NASA’s science programs, extended missions are an important part of both achieving decadal science objectives and determining priorities or approaches for future exploration. This report also finds that senior review is the best mechanism for advising NASA about budgetary levels or advising when a mission should be terminated because its scientific return is not commensurate with the requisite investment. As such, decadal surveys do not typically weigh in on individual operating missions. However, SOFIA was not considered by the last Senior Review panel, and the value of continuing operations of SOFIA beyond 2023 is of concern with respect to the other priorities of this report.

5.2.1 SOFIA

In the budget presented to Astro2020, NASA did not include plans to continue operating SOFIA beyond 2023. NASA conducted two separate review exercises: the SOFIA Operations and Maintenance Efficiency Review (SOMER) and the SOFIA Five Year Flagship Mission Review (FMR). The decadal survey, as part of its overview of the current state of astronomy and astrophysics science and technology research, considered the outcome of these reviews and made its own evaluation of the scientific value of continuing SOFIA relative to Astro2020 science questions, and relative to other decadal survey priorities.

SOFIA, prioritized by the 1990 and 2000 decadal surveys, observes with an air-temperature 2.5 m telescope mounted in a highly modified Boeing 747. It typically flies at altitudes over 11.3 km, which is above 99 percent of Earth’s precipitable atmospheric water vapor, allowing for access to infrared wavelengths not possible from the ground. SOFIA’s instrumentation has therefore focused on mid- to far-infrared, via both spectroscopy and imaging. SOFIA is a joint project of NASA and Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR, the German Space Agency), with NASA providing 80 percent of operations costs and DLR 20 percent. The SOFIA program was started under contract with the Universities Space Research Association in 1996, saw first light in May 2010, and achieved full operational capabilities in May 2014. SOFIA performs mostly northern hemisphere flights, as it is based in Palmdale, California, and spends a smaller fraction of the year in the southern hemisphere, where it takes off from Christchurch, New Zealand.

The survey committee has significant concerns about SOFIA, given its high cost and modest scientific productivity. The NASA portion of SOFIA’s operating budget is $86 million a year, of which $4 million goes to guest observers for data reduction and analysis. This yearly budget is in a range comparable to NASA’s flagship space telescopes Hubble and Chandra ($98 million and $62 million in fiscal year 2019, respectively). The total life cycle cost for SOFIA to date is ~$1.5 billion. For this investment, the science productivity to date is very low: 178 total papers after 6 years (from May 2014 to May 2020). The science impact is also low; these papers have a relatively low citation rate: for the same time period, only 1,242 citations. As a comparison, in the first 6 years after the launch of each of Hubble and Chandra, with similar yearly budgets, the community produced more than 900 and 1,800 total papers, respectively. Similarly, the European Space Agency’s Herschel mission, was, like SOFIA, a flagship scale mid-to-far-infrared facility,

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12 National Academies of Sciences, Engineering, and Medicine, 2016, Extending Science: NASA’s Space Science Mission Extensions and the Senior Review Process, The National Academies Press, Washington, DC, https://doi.org/10.17226/23624.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×

which saw nearly 900 peer-reviewed papers in the 6 years following launch (170 papers in the first year alone), with more than 20,000 citations during the same period. Comparing to a more recent mission that has been operating for a shorter time than SOFIA, NASA’s TESS—a Medium-Class Explorer mission—had in its first 2 years of operations (launch date April 2018) 281 papers with 2,322 citations. In addition, SOFIA’s clearly unique capabilities across these important wavelength ranges have not translated into high utilization of the observatory by the astronomical community. For instance, only 9 of the 35 SOFIA-related Ph.D.s are from U.S.-based students, as of fall 2019, and the single largest producer of SOFIA’s scientific publications to date is Germany’s Max Planck Institute for Astronomy. Furthermore, some of the originally motivating unique capabilities in 1990 and 2000 have since been superseded by the results from the Herschel Space Observatory (2009–2013). Relative to its cost, SOFIA has not been scientifically productive or impactful over its duration.

To assess SOFIA’s potential impact going forward, the committee determined the role that SOFIA could play in Astro2020 science priorities. The committee also found that SOFIA directly addresses 3 of the 30 priority science questions (Question 4 of the Panel on Galaxies; Question 2 of the Panel on the Interstellar Medium and Star and Planet Formation [ISM]; and Question 4 of the Panel on Stars, the Sun, and Stellar Populations), and indirectly contributes to one more (Question 4 of ISM). There is therefore minimal overlap of the Astro2020 panels’ science priorities with SOFIA capabilities.

Some of SOFIA’s challenges are inherently structural. The operation of the observatory is complex, and a large staff is required both to maintain the observatory and to perform observing runs. There is significant down time in each year for necessary airplane maintenance. With a typical ~1,000 flight hours per year, and a relatively modest 60 percent of programs being completed, and 60 percent of these turning into peer-reviewed publications, only a few percent of total yearly calendar hours are turned into peer-reviewed science, an order of magnitude less than other astronomical observatories.

In 2018–2019, NASA charged two review committees to assess the state of SOFIA. These were SOMER and FMR, the latter of which primarily focused on science. The SOMER review made a number of recommendations for fundamental changes to management and operations to improve flight-hour production and reduce costs. The FMR review suggested that transformative change was needed, with a strong need to alter planning and decision making so that it is more science-focused. The FMR gave a number of recommendations for completing high-priority science programs and delivering high-quality data.

The survey committee found no evidence that SOFIA could, in fact, transition to a significantly more productive future. There have been only modest improvements in productivity over the past 2 years. These include a 50 percent increase in papers per year, and a higher completion percentage of high-priority programs. A new director was also recently appointed. It is noted, however, that the SOFIA team has responded to NASA that a number of major recommendations from the SOMER and FMR reviews are not feasible to implement, suggesting that any future improvements would still be modest and insufficient to bring about the flagship-level science associated with its budget. Thus, the survey committee found no path by which SOFIA can significantly increase its scientific output or relevance to a degree that is commensurate with its cost.

Conclusion: The cost of SOFIA’s yearly budget is comparable to NASA’s Hubble and Chandra flagship missions, yet the scientific productivity is significantly lower. There is no evidence that SOFIA could transition to a significantly more productive scientific future.

Recommendation: NASA should end SOFIA operations by 2023, consistent with NASA’s current plan.

Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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Suggested Citation:"5 Evaluating and Balancing the Operational Portfolio." National Academies of Sciences, Engineering, and Medicine. 2023. Pathways to Discovery in Astronomy and Astrophysics for the 2020s. Washington, DC: The National Academies Press. doi: 10.17226/26141.
×
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We live in a time of extraordinary discovery and progress in astronomy and astrophysics. The next decade will transform our understanding of the universe and humanity's place in it. Every decade the U.S. agencies that provide primary federal funding for astronomy and astrophysics request a survey to assess the status of, and opportunities for the Nation's efforts to forward our understanding of the cosmos. Pathways to Discovery in Astronomy and Astrophysics for the 2020s identifies the most compelling science goals and presents an ambitious program of ground- and space-based activities for future investment in the next decade and beyond. The decadal survey identifies three important science themes for the next decade aimed at investigating Earth-like extrasolar planets, the most energetic processes in the universe, and the evolution of galaxies. The Astro2020 report also recommends critical near-term actions to support the foundations of the profession as well as the technologies and tools needed to carry out the science.

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