NASA has announced that it's the new owner of two ready-made space telescopes, courtesy of a government intelligence agency. But like many gifts, they aren’t exactly free.
Charity isn’t dead in the cold, bureaucratic hallways of the federal government. Earlier this week, astronomers announced that the National Reconnaissance Office (NRO) offered NASA a pair of declassified space telescopes last year, free of charge. They have the same aperture as Hubble. The NRO, which oversees U.S. spy satellites, had deemed the telescopes unsuitable for intelligence missions, and they have been sitting in a warehouse in Rochester, New York, ever since.After taking a close look at the scopes, NASA accepted. The telescopes, unofficially dubbed NRO-1 and NRO-2, represent a unique opportunity to advance science with relatively modest impact on NASA’s beleaguered bottom line: they are high-quality instruments with state-of-the-art optics and the ability to house instruments supporting a wide variety of science missions. Each has a superb, 1/20th-wave 2.4-meter (7.9-foot) primary mirror. They are shorter and stubbier than Hubble, with f/1.2 primary mirrors compared to Hubble's f/2.3 primary. But that means they could potentially have a field of view up to a hundred times larger.
Though designed for looking down at the ground, they are “optically perfect,” says Alan Dressler (Carnegie Observatories), and could provide an excellent wide-field complement to Hubble and the oft-delayed James Webb Space Telescope.
One catch: they come with no instruments on the back end — no cameras, spectrographs, or anything.
Although getting the NRO telescopes equipped and into space anytime soon is unlikely at best, even one of them could help to fulfill some of the goals of the 2010 Astronomy and Astrophysics Decadal Survey, a list of astronomers' top priorities for the next ten years. At the top of this wish list was the Wide-Field Infrared Survey Telescope (WFIRST) project, which would address several high-priority science programs such as investigating dark energy, performing infrared sky surveys, and hunting for exoplanets.
Astronomers had envisioned WFIRST as a 1.5-meter wide-field telescope, but the 2.4-meter NRO-1 could easily fill the role: depending on configuration, the telescope could have a field of view about the same as WFIRST’s but could see objects twice as faint.
That capability would make it a good partner for the James Webb Space Telescope (JWST) in observing the infrared sky. With a larger field of view but lower sensitivity, NRO-1 could pick out interesting targets through surveys that JWST could then home in on with its narrower, deeper, sharper view.
But NRO-1 would be far from free. Just as a winning contestant on The Price is Right pays income tax and maintenance for her “free” Mustang convertible, a host of costs come with the new scope. Dressler, who briefed a National Academy of Sciences committee in Washington, D.C. on potential uses for the telescopes earlier this week, says there are three things necessary to get NRO-1 into space.
First is instrumentation. The telescope today consists mainly of optics and housing, having relinquished its secret spy components before leaving the NRO’s control. Engineers would need to install instruments such as cameras, spectrographs — possibly with further optics — to equip the scope for science missions.
The second is spacecraft capability. The telescope needs a body to house thrusters and communications, gather power via solar cells, and regulate temperature and perform other housekeeping tasks. Those functions are “the name of the game,” says Dressler. “The rest of the telescope just kind of sits there, and electrons move.”
Lastly, the scope needs to get into space, which with the Shuttle program terminated may be the largest hurdle to overcome. Working in its favor is that NRO-1 is a fraction the weight of Hubble, and therefore less expensive to launch. Dressler speculates that tests of NASA’s Space Launch System may provide a serendipitous way to get NRO-1 into orbit. Private-sector launch vehicles such as SpaceX’s Falcon 9 could work as well. Still, the telescope’s path to space remains unclear.Each of these obstacles will cost $100 to $200 million to overcome by Dressler’s estimate. Still, the optics and housing—which NASA now already has — comprise the bulk of the cost of building a space telescope, and Dressler estimates that NRO-1 could be put into service for about $1 billion. That's roughly one third of Hubble’s pre-launch construction bill in 2012 dollars.
Still, cash-strapped NASA doesn’t have the money: much of its astronomy budget is tied up in the costly, perennially delayed JWST. Any launch of NRO-1 is tied to the success of JWST, says Dressler. Assuming the (currently) $9 billion JWST is completed and deployed by 2018, as its latest schedule aims, Dressler thinks NRO-1 could be put into service by 2020 or 2022 — just in time for the next Decadal Survey.
If NASA can launch NRO-1 for $1 billion and do it on a tight schedule — a big if, given the agency’s record — it could open the way for astronomers to successfully pitch NRO-2 for use as more than a mothball collector. A lot of future science may be sitting in a warehouse in Rochester right now.