“It’s not too early,” NASA Astrophysics Division Director Paul Hertz said of the timeline for the studies. “We need to identify some missions for after WFIRST in order to start making technology investments.”
SEATTLE — While the final report is still more than five years away, NASA has effectively kicked off the next astrophysics decadal survey by asking the scientific community to evaluate ideas for the next large mission that the report may recommend NASA pursue in the 2020s.
In a presentation here Jan. 4, NASA Astrophysics Division Director Paul Hertz formally asked three program analysis groups that support the astrophysics subcommittee of the NASA Advisory Council (NAC) to review a shortlist of candidate missions that the agency will select by the end of this year for mission concept studies that will support the next decadal report, to be completed in 2020.
“I’m charging the three program analysis groups with looking at the list of missions which we are putting forward and providing community input on whether that is the right set of missions to NASA to study leading into the next decadal survey, or whether we should study a different small set of missions,” Hertz said at a joint meeting of the three groups.
NASA’s initial list of missions comes from the 2010 decadal survey as well as a 30-year strategic roadmap document the division published in late 2013 that identified some of the key scientific goals for the next three decades and the missions required to achieve them. Those missions include:
- Far Infrared Surveyor: A space telescope that would operate at long infrared wavelengths and have greater sensitivity and resolution than missions like the Spitzer Space Telescope or the European Space Agency’s Herschel Space Telescope.
- Habitable-Exoplanet Imaging Mission: A space telescope that would be able to directly observe an Earth-like extrasolar planet orbiting another star, using technologies to block light from the star itself.
- Ultraviolet/Optical/Infrared Surveyor: A space telescope with a mirror of eight to 16 meters in diameter, building upon both the Hubble Space Telescope and James Webb Space Telescope.
- X-Ray Surveyor: An X-ray observing space telescope that would provide greater capabilities than the existing Chandra X-Ray Observatory and ESA’s XMM-Newton spacecraft.
Hertz asked the program analysis groups to provide reports by the fall 2015 meeting of the NAC astrophysics subcommittee regarding which of those missions, if any, should be replaced by alternative concepts. The subcommittee will then provide NASA with its recommendations regarding which missions to study.
He cautioned scientists, though, not to add a large number of other missions to the list. “I don’t think I need to study ten for the decadal survey,” he said. “I only want to study missions that I think have a realistic chance of getting the number one recommendation from the next decadal survey.”
Hertz said by the end of the year he will pick three or four missions for concept studies, evaluating both the science goals of the missions and their technology development needs. NASA will also perform independent cost assessments of each mission concept.
The goal is to complete the studies late in the decade to support the 2020 decadal survey, which will start in 2018. The studies are intended to give decadal survey panelists information about both the capabilities and risks of potential missions before recommending one as the highest-priority large mission for the 2020s.
The studies, Hertz said, are intended “to make the 2020 decadal survey as effective as possible.” However, there’s no guarantee those working on the decadal survey will pick one of the missions studied as its No. 1 large mission. “The decadal survey will consider what they want to do with this input,” he said. “It’s not NASA’s job to tell them how to do their review.”
NASA followed a similar approach for the 2010 decadal survey, performing studies of several mission concepts. One of those concepts, called the Joint Dark Energy Mission, evolved into the Wide Field Infrared Survey Telescope (WFIRST), which the 2010 decadal picked as its highest priority large mission.
Since the 2010 decadal, NASA has continued to study WFIRST, including investigating the use of one of two 2.4-meter telescopes provided to NASA by the National Reconnaissance Office. A formal new start for WFIRST is planned for no earlier than fiscal year 2017, Hertz said.
Similarly, work on the mission the 2020 decadal picks as the top large mission would likely not begin until the mid-2020s and not launch until the 2030s. Despite that long-time horizon, Hertz said now was the time to start thinking about such missions and their technology requirements.
“It’s not too early,” he said of the timeline for the studies. “We need to identify some missions for after WFIRST in order to start making technology investments.”
