Geek Trivia: A waste of space (program)

How was the second backup primary mirror for the Hubble Space Telescope -- an optic that could have replaced the flawed mirror that famously hobbled the Hubble, had the problem been caught before the spacecraft was launched -- creatively "recycled?"

How was the second backup primary mirror for the Hubble Space Telescope -- an optic that could have replaced the flawed mirror that famously hobbled the Hubble, had the problem been caught before the spacecraft was launched -- creatively "recycled?"

The second backup to the Hubble's primary mirror is now the central optic of the 2.4 meter SINGLE Telescope at the Magdalena Ridge Observatory in New Mexico. After all, when you have access to one of the three most precisely ground optical telescope mirrors ever created -- and one of only two that were ground correctly -- there's no sense in not making a really nice telescope out of it. The SINGLE went online Sept. 1, 2008 and is currently under contract with NASA to track Low Earth Orbit (LEO) objects and to support the operations and observations of the Fermi Gamma-ray Space Telescope.

And should anything happen to the SINGLE's main mirror, they can always ask the Smithsonian's National Air and Space Museum if they'd be willing to lend out the other backup Hubble mirror from their collection to do some actual astronomy.

So why did NASA build three copies of the same mirror? As a guard against a problem in the manufacturing process, ironically. Camera giant Kodak and Itek, a manufacturer of spy satellite optics, originally submitted a tandem bid for the Hubble mirror. Each company would manufacture its own optic, and then each would check the other's work for accuracy.

Perkin-Elmer won the contract over the Kodak-Itek team because Perkin-Elmer promised to use a then-cutting-edge computer-controlled grinding process to ensure the mirror's accuracy. NASA desired the promised quality of a computer-created mirror, but as the technology was brand new, it required Perkin-Elmer to subcontract with a traditional manufacturer to create a conventional backup mirror, just in case. The backup manufacturer turned out to be the Kodak-Itek team. Thus, three mirrors were made, but only the flawed computer-"aided" one would end up in space.

While the computer-ground mirror was flawed, it was at least precisely flawed, such that NASA could design the Corrective Optics Space Telescope Axial Replacement (COSTAR), which serves as corrective lenses for the Hubble's main mirror. COSTAR was installed in December 1993, over two and a half years into Hubble's mission, and will be removed during the final servicing mission to the Hubble in mid-2009 in favor of the Cosmic Origins Spectrograph. After that, the Hubble will likely never be touched by human hands again and consistently observed only by those who track objects in Low Earth Orbit. Like, for example, the astronomers running the SINGLE Telescope, and its Hubble-donated mirror.

That's not just some apropos orbital observation; it's a remarkably retrospective reflection on Geek Trivia.

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