NASA Soon To Judge Spy Telescope’s Suitability for JWST Follow-On
WASHINGTON — NASA will soon decide whether it is worth using one of the two Hubble-sized space telescopes it got from the U.S. National Reconnaissance Office last year for a dark-energy survey mission the National Academy of Sciences recommended as a follow-on to the James Webb Space Telescope (JWST).
NASA Administrator Charles Bolden was briefed May 30 on a report that concluded the partially completed spy telescopes with 2.4-meter primary mirrors — the same diameter as Hubble’s — offer a “feasible and affordable” way for NASA to complete the Wide-Field InfraRed Survey Telescope (WFIRST) — a mission designed to fulfill science objectives that in 2010 the National Academy of Sciences said were second only to those being tackled by JWST.
A NASA source said an announcement about the possible mission was planned for the week of June 3.
The task of briefing Bolden May 30 fell to Paul Hertz, director of NASA’s Astrophysics Division, spokesman J.D. Harrington said May 29. Hertz presented a report published May 24 by the Wide-Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets science definition team, and Bolden will now decide whether to keep the door open for a WFIRST built around the donated spy hardware.
“They’re having a meeting ... where they’ll say, ‘Yes, we think there’s science value,’ or, ‘No, we don’t think there’s science value,’” Neil Gehrels, chief of the astroparticle physics laboratory at NASA’s Goddard Space Flight Center in Greenbelt, Md., told SpaceNews after a May 28 Maryland Space Business Roundtable luncheon. Gehrels co-chaired the team that wrote the report Hertz will present to Bolden.
Bolden’s decision will not determine whether there will be a WFIRST mission, but what the mission might look like if NASA can find funding for it. Compared with another WFIRST concept NASA has examined, the surplus spy hardware has a larger primary mirror and room for extra science instruments.
A WFIRST mission concept published by NASA in July 2011 proposed an observatory with a primary mirror 1.3 meters in diameter, which would cost an estimated $1.63 billion to build from scratch.
Gehrels’ team did not provide a cost estimate for the larger WFIRST concept it proposed, but the team’s report said its concept was “simpler and lower risk” than the one in the 2011 study. Design and development of a WFIRST built around one of the gifted telescopes would take about eight years, of which development of the primary infrared imaging instrument would account for just over four.
Whatever NASA decides, the agency, as Hertz has said multiple times, will not be able to start work on another big astrophysics mission until 2017, when JWST’s development starts winding down. NASA expects to spend $8.8 billion on JWST by the time it has been on orbit five years. The massive space observatory is slated to launch in October 2018 aboard a European Space Agency-provided Ariane 5 rocket.
NASA has said that at least one of the two donated spy telescopes, which are currently being stored at the space agency’s expense at ITT Exelis Geospatial Systems of Rochester, N.Y., will be put up for grabs by any part of the agency — not just the astrophysics division. The only restriction is that they cannot be used for Earth observation, a use the National Reconnaissance Office forbade as a condition for giving NASA the unwanted hardware, which sources have said was built for a failed spy satellite program dubbed Future Imagery Architecture.
NASA solicited mission concepts for the telescopes back in November and distilled the many responses it received into seven narrower categories that were presented to senior agency officials back in February. These included putting a telescope in orbit around Mars, tuning a telescope for ultraviolet imaging and turning the former spy hardware into an optical communications node.
A summary of these and other concepts, and NASA’s initial analysis of them, was to have been completed in May and is due to be published soon, according to a website NASA set up for the so-called Study on Applications of Large Space Optics.