Hubble is winking out

NASA/ESA/Hubble Heritage, star-forming region NGC3603, SpaceTelescope

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Hubble, aka the HST, has given us hundreds, maybe thousands of images of space, like the one above. But it's reaching the end of its lifetime. Scientists say it could  survive through 2020. Many of us watched with great interest as it was being built. A synopsis of Hubble's story is available at the Hubble site. Its optics are amazing. For a detailed description of the telescope's construction, check out Science Clarified's article. Unfortunately, Hubble's mirror in the newly deployed device "was the wrong shape and could not focus properly (Science Clarified)". If you're interested in such here's a link to NASA's Optical Systems Failure Report (a large PDF).

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Grinding the Hubble mirror, Science Clarified

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Hot in the news right now is a possible replacement for Hubble, one that doesn't require grinding mirrors or transporting a payload of 24,500 pounds. It's called the Aragoscope, and its technology is revolutionary (when is space technology not?). It's being developed at the University of Colorado-Boulder and scientists there say that it could "provide images up to 1,000 times sharper than the Hubble Space Telescope." This is an illustration of the concept.

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WebsterCash, Aragoscope illustration, Centauri Dreams

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The idea originates with Webster Cash and he describes it thus in an article at Centauri Dreams:

Unlike a starshade, the Aragoscope would be circular in shape, an opaque disk whose diffracted light is directed toward a pinhole camera at its center, then to a telescope that provides extremely high resolution views of stellar objects.  

Cash has also developed the starshade concept, but is now calling the Aragoscopy phase 2 of his efforts to develop a new kind of telescope. Paul Gilster at Centauri Dreams comments:

It’s intriguing that the Aragoscope, in some ways, turns Cash’s earlier starshade concepts on their head, aiming for high resolution rather than high contrast. “I spent a lot of time understanding the physics of destroying diffractive waves very efficiently,” he told the magazine. “In the process, it’s not hard to see that you can use those detractive waves to create images.”

Deploying the Aragoscope would be much simpler to launch than the HST, as described by CBS:

The opaque space disk would be made of a strong, dark, plastic-like material (think Hefty bag) that could be launched in a compressed fashion like a parachute, and then unfurled in orbit. The space shield would be tethered to the telescope at distances from tens to hundreds of miles depending on the size of the disk, said Harness [doctoral student Anthony Harness of the Department of Astrophysical and Planetary Sciences].

More information is available at Gizmag and Popular Mechanics.

-- Marge