ST. LOUIS — As astrophysicists prepare to begin their next decadal survey, other scientists and members of Congress endorsed the overall process even as they suggested some changes.

At a town hall meeting during the 234th meeting of the American Astronomical Society here June 11, leaders of the latest astrophysics decadal survey, dubbed Astro2020, said they’re ready to begin work identifying scientific priorities in the field for the coming decade and what spacecraft and ground-based observatories are best suited for them.

Robert Kennicutt, an astronomer at the University of Arizona and Texas A&M University who serves as co-chair of Astro2020, said the National Academies, which oversees the decadal survey, received more than 450 nominations to serve on the steering committee Astro2020 decadal survey. Ultimately the National Academies selected 20 people, counting Kennicutt and fellow co-chair Fiona Harrison of Caltech, to serve on the committee.

The steering committee is populated primarily by astronomers, but Kennicutt noted it includes a few outside experts, such as former Lockheed Martin executive Wanda Sigur. “We wanted, in addition to astrophysicists on the committee, two or three technical experts,” he said, who can provide advice when evaluating proposed observatories and spacecraft missions.

The steering committee will hold its first meeting in Washington July 15–17. The committee is currently working on identifying members for 13 panels that will support the committee’s work. Six of those panels will focus on science issues, from cosmology to exoplanets, while another six will address programmatic topics, like the missions needed to carry out that science. The thirteenth panel is devoted to an assessment of the state of the profession.

The committee and its supporting panels will, as part of their initial work, review hundreds of science white papers submitted by astronomers. Kennicutt said the committee received about 590 white papers, nearly double the number from the previous decadal survey. A separate call for white papers on activities, projects and the state of the profession is underway, with papers due next month.

The five-week partial government shutdown at the beginning of the year had “ripple effects” on the schedule for Astro2020, he said. The goal had been to release the final report in late October 2020, “but it’s looking increasingly likely that we will not meet that deadline.” He said the report will now likely come out in early 2021, avoiding the 2020 general election.

The decadal surveys in astrophysics and other space sciences are treated with almost reverence by not just the astrophysics community but also funding agencies like NASA and by Congress. That’s because the reports offer a consensus position on what missions and other programs the scientific community believes should be supported.

That’s required, though, continued advocacy, said Harrison, a former chair of the National Academies’ Space Studies Board. “Having been chair of the Space Studies Board, part of what I considered my job was to go around and explain to constituencies on the Hill the value of decadal surveys across all of the disciplines,” she said.

The same day as the astrophysics town hall meeting, the space subcommittee of the House Science Committee addressed the value of decadal surveys during a hearing on NASA’s science programs.

“NASA’s Science Mission Directorate has benefitted from a systemic approach to setting priorities that guide NASA’s planetary, heliophysics, astrophysics and Earth science program over 10 years,” said Rep. Kendra Horn (R-Okla.), chair of the subcommittee, in her opening statement. “The decadal surveys keep us honest and focused on top priorities when funding constraints or competing interests arise.”

Scientists who were witnesses at the hearing agreed with that assessment. “Many of NASA’s most important activities, from Mars exploration to studying extrasolar planets to understanding the cosmos, are centuries-long projects, the modern version of the construction of the great medieval cathedrals,” said David Spergel of Princeton University. “The decadal surveys provide blueprints for constructing these cathedrals, and NASA science has thrived by being guided by these plans.”

“You end up having the consensus opinion of multiple communities within Earth science,” said Chelle Gentemann, co-chair of the Space Studies Board’s Committee on Earth Science and Applications from Space. “This is a very difficult and thoughtful process, which is why the community stands behind it strongly.”

Without a decadal, “our development becomes more constrained by political considerations than science considerations,” said Mark Sykes, chief executive and director of the Planetary Science Institute.

The process, though, is not perfect, Sykes added. “If it was up to me,” he said, “I would allow public comment on the committee reports and the steering committee report because things are finalized.”

Another issue, he said, is that there’s too much focus paid on recommendations for large-scale, or flagship, missions in those decadal reports. “Often we’re too distracted by the bright shiny objects, the largest projects recommended by the decadals,” he said. “We need to pay attention to the little stuff, too.”

Kennicutt, at the town hall meeting, agreed, noting that one of the panels for Astro2020 will examine foundational issues to support research versus specific proposals for observatories or spacecraft. “There’s almost sometimes too much of a fixation on the great big giant projects and ranking them, and not enough attention to the stuff we’re mostly involved with: theory, computation, simulation, lab astrophysics, technology development,” he said. “Are there things, other than funding individual big things, where some strategic investment over the next decade will help realize the science?”