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Thursday, June 7, 2012

NASA gets two Hubble-class telescopes from the military

NASA has been given two ex-spy satellites with optics superior to those of the Hubble Spac...
NASA has been given two ex-spy satellites with optics superior to those of the Hubble Space Telescope seen here (Photo: NASA)

NASA’s collection of space telescopes just got a bit bigger thanks to an extraordinary gift from America's National Reconnaissance Office (NRO) intelligence agency. The space agency announced on Monday that the NRO has given it two surplus spy satellites that are more advanced than the Hubble Space Telescope. If the money can be found for a mission for the spy “birds” then NASA will not only have two possible
replacements for the retiring Hubble, but also an added ability to scan the skies for supernovae, locate new exoplanets and even seek the answer to the fate of the universe.
The spy satellites, which have never flown, are in storage in Rochester, NY. They were part of America’s military-intelligence space program run by the Department of Defense and the intelligence services - something the world gets a glimpse of when the U.S. Air Force lifts the veil on its X-37 space plane ... or the NRO shows that it has a couple of Hubble-class orbital telescopes going spare.
NASA’s Hubble Space Telescope took decades of development, funding problems, setbacks and missed launch dates before finally getting into orbit, only to have a design flaw discovered that required a Space Shuttle visit to put right. Now that the Hubble is reaching the end of its service life, its successor, the James Webb Space Telescope, is going through a replay of the same problems.
Though the NRO satellites have been officially declassified, the complex rules about secret material, plus a reluctance to tip what the satellites are capable of, means that many details about them have not been made public. Not even their names have been revealed, but from descriptions they appear to be some variant of the KH-11 Kennan spy satellites that the Pentagon has been flying since 1975. This pair were probably built in the 1990s or slightly later.

"Stubby Hubbles"

Described by NASA as “Stubby Hubbles,” the spy satellites weigh in at 1,700 kg (3,700 lb) and look like a cross between the Hubble and a dustbin. The optics are superior to the Hubble’s, which is impressive, since the Hubble can see a dime perched on top of the Washington Monument. The satellites have the same 94-inch diameter primary mirror as the Hubble, though with a much steeper curvature. They also have a much shorter focal length than the Hubble, allowing them to scan a much wider field of vision. Unlike the Hubble, they also have a maneuverable secondary mirror for better focus. There is also more room in the stern of the satellites than the Hubble for mounting instruments.
And the catch? While it may seem a great windfall for NASA to have a couple of super-Hubbles fall into its lap, when they were first given to NASA they were looked upon as a couple of white elephants. They may have had superior optics, but not much else. The NRO had stripped the satellites of everything still on the secret list and what was left didn’t even have solar panels or an attitude control system. Worse, the transfer of ownership was merely the handing over of a piece of paper saying that they were now NASA’s, so the satellites remained in upstate New York and NASA was stuck with US$1,000,000 a year in storage costs. That’s not small change for a pair of half-there satellites that no one knew what to do with.
Then John Grunsfeld, ex-astronaut and NASA’s associate administrator for space science had a brainstorm. Ideas had already been put forward to use them for hunting extra-solar planets or keeping an eye out for supernovae, but he suggested something bolder - studying dark energy.

Dark energy

Dark energy is a hypothetical energy that some scientists believe explains a fundamental mystery of the universe. Because of how the cosmos works and how much matter is in it, the expansion of the universe after the Big bang should have slowed down about five billion years ago as the particles that make up matter start to attract one another with a force stronger than the force of expansion. This hasn’t happened. In fact, the expansion has actually sped up. Why this is happening remains a mystery, but one hypothesis is that the universe is permeated with an undetectable form of “dark energy” that makes up about 73 percent of all the matter and energy in the universe. This dark energy acts as a counter attractant and stretches the universe apart like a gigantic taffy pulling machine.
This has some fairly dire implications because if the expansion continues, then the galaxies will be stretched so far apart and be moving so fast in relation to one another that one day our galaxy may find itself alone in its own pocket universe where it will burn itself out. The alternative is that the dark energy ends up just ripping all the matter in the universe apart in the end, which isn’t very pleasant either.
NASA already has a project for studying dark matter called WFIRST, which stands for Wide Field Infrared Survey Telescope. The only problem is the WFIRST seems hopelessly stalled with a price tag of US$1.5 billion, a launch date of 2024 and the need to lift the spacecraft into a very expensive solar orbit. Grunfeld thought that the spy satellites, with their ability to view in the infrared range, might be a viable alternative to WFIRST and when he showed the craft to the WFIRST spacecraft engineers, they reportedly said: “Don’t change a thing.”
Using the spy satellites would certainly give WFIRST a boost. Having two ready-made craft, a mission craft and a back up, already at hand saves NASA US$250 million and moves the launch window forward to 2020. Equally important, the spy satellites can do the job from geosynchronous orbit around the Earth, which is much cheaper to reach than solar orbit.
As of now, this mission is still just an idea and will remain so until Congress decides whether or not to fund it. Then the satellites need to be modified and completed, so there is a long way to go.

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