What does it look like when one of the US government’s most secretive agencies has a garage sale? Something like this: today the National Reconnaissance Office (NRO) announced that it has given NASA not one but two fully-constructed space telescopes, roughly equivalent to Hubble with a wider field of view. The telescopes, which were offered to NASA about a year ago (a team of scientists has been considering whether to accept them in the meantime), come with all their hardware minus instruments – a total value to the agency of hundreds of millions of dollars plus years of lead time.
The two telescopes – as yet unnamed; given their provenance, I humbly propose “Boris” and “Natasha” – have been described as “stubby Hubbles.” They have the same primary diameter mirror as Hubble (2.4 m), but are optically faster – have a shorter focal length – and hence have a wider field of view. They also have a movable secondary mirror, allowing for improved off-axis performance. This design is about what would be expected from a recon satellite meant to survey large chunks of the Earth below, and it makes these two telescopes perfect for wide-field survey missions.
WFIRST, which has already claimed one of the telescopes, plans to conduct a number of sky surveys, including near-IR wide-field imaging, photometry monitoring for microlensing, and imaging and spectroscopy of a large sample of galaxies for dark energy research – all ideal applications for such a telescope. The WFIRST mission, which absorbed the Joint Dark Energy Mission (JDEM), was ranked as top priority by the Decadal Survey but until now had been written off as a victim of JWST-induced budget cuts. The original mission was planned around a 1.5 m telescope, but the heart of the design is the wide-field infrared camera; the instrument design can be easily adapted to the new 2.4 m diameter and would provide 100x the area of view of Hubble’s WFC3/IR instrument. The only problem arises from the mirror coating – designed more for optical observing, it cuts off infrared wavelengths at 2.175 microns, as compared to the 2.4 microns the science team would like. The second telescope hasn’t yet been assigned to a mission, but it could conceivably be used for transient-finding, exoplanet detection, or any other astronomical application that requires a wide field of view.
Civilian space-based astronomy and military space-based reconnaissance have a long and tangled relationship that goes back almost to the first days of spaceflight, when NASA’s Ranger, Lunar Orbiter, and Mariner exploration programs borrowed the Agena booster stage developed for the secret CORONA reconnaissance program. The original Hubble itself is essentially a copy-paste of the KH-11 Kennan (later Crystal) reconnaissance satellite – when astronomers were selecting the final design of the telescope, Lockheed asked them to change the primary from the planned 3m to its current 2.4m because they mysteriously already had the facilities in place to fabricate mirrors of that size. The development of the CCDs that revolutionized astronomy (as well as making your cameraphone possible) was also largely underwritten by the reconnaissance community.
As for Boris and Natasha in particular, I’d guess they were either backups for an old program that’s been terminated or prototypes for a program that never launched. When building a project that has a number of satellites, the agency builds many more satellites than it plans to launch. Some number of satellites will be lost on launch; boosters these days are highly reliable, but there’s always a chance. Even once it gets up there, the satellite can fail to deploy correctly for any number of reasons – a bad push from the upper stage, fouled solar panels, damage on launch. And some number of satellites will fail early for whatever reason and need to be replaced quickly. As a result it’s always a good idea to build more birds than you’re planning to launch, especially for a reconnaissance program that can’t afford gaps in coverage. It may be that the NRO has had these telescopes sitting in storage for a while; their comparable size to Hubble implies that they were also constructed in the mid-80s to mid-90s timeframe. The agency probably got sick of the upkeep cost to keep the telescopes in storage, and looked around to see who else might want to take them on.
While a windfall for the cash-strapped NASA, don’t expect to see the two telescopes riding a rocket to orbit anytime soon. The hardware handed over to NASA comprises just telescopes, not spacecraft – they lack some of the hardware necessary to operate in space, and of course they don’t come with scientific instruments, either. Some sources say that they might be missing critical hardware such as solar panels or pointing systems, and the communications systems may not be on the NASA standard designed to interface with their existing ground networks. When the NRO first offered the telescopes to the agency, it wasn’t even sure it would accept them. The telescope hardware itself represents about a quarter to a half of the full price tag of a mission, and NASA wasn’t sure it would have the resources to get teams organized around the hardware and pay for the rest of the mission. It’ll be at least 2020 before one of these satellites is up in space taking data. But they still represent an enormous time and money savings. With two frameworks in place, scientists can get right down to building instruments – and it’s harder to defund a program that already has so much hardware in place (a sad consideration, but one that must be taken into account).
While it’s sweet of the NRO to think of NASA and donate such nice hardware to the cause of science, I will admit that it does gall me a bit that NASA has to scramble for funding and gut healthy projects to keep one telescope alive while the NRO has enough cash to keep two on ice, then hand them out like a friend giving away a TV before he leaves town. Still, can’t complain too much about someone who gives us such nice presents. Since the donation was just announced today, we’ll have to wait a couple of weeks to watch it play out within NASA and see how the mission staffs end up organized. With any luck Boris and Natasha will have their pasts erased, Bourne-style, and start a new life as productive scientific tools.