SaaS data loss: The problem you didn’t know you had
The Wide Field Camera 3 (WFC3, pictured), meanwhile, will be set to work on "a broad range of inquiry, from early and distant galaxies beyond Hubble’s current reach".
The instrument's key feature is its "ability to span the electromagnetic spectrum from the near ultraviolet through the optical ... and into the near infrared". It will be the only Hubble kit with this "panchromatic" talent, NASA explains, and could provide "the greatest era in the spectacular history of Hubble imaging".
NASA elaborates: "The incoming light beam from the Hubble telescope is directed into WFC3 using a pick-off mirror, and is directed to either the Ultraviolet-Visible (UVIS) channel or the Near-Infrared (NIR) channel. The light-sensing detectors in both channels are solid-state devices.
"For the UVIS channel a large format Charge Coupled Device (CCD), similar to those found in digital cameras, is used. In the NIR detector the crystalline photosensitive surface is composed of mercury, cadmium and tellurium (HgCdTe)."
Rather more mundane items aboard Atlantis will be a new set of six gyros to ensure Hubble's "very precise pointing requirements", two battery modules (pictured) to "rejuvenate the electrical power system" and an "outer blanket layer". The latter, comprising stainless steel sheets, will be installed on the telescope's exterior to "provide additional thermal protection to some equipment bays, replacing the existing multilayer insulation which has slowly degraded over time due to the harsh environment of space".
The Atlantis crew will also carry out repairs to Hubble's Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph. There are full details on all the planned activities available via the main Servicing Mission Four site. ®
COMMENTS
Re: Standby...
Discovery is still up there, due back tomorrow so I guess they'll be too busy dealing with that one to be getting Endeavour ready (which itself is probably being prepared for it's ISS mission in June).
A fitting tribute to the shuttle and Hubble
The shuttle might have proved an expensive and not entirely reliable way in to space, but this is the sort of job it excels at, and this mission is a fitting tribute to the closing stages of both it and the telescope's life. Without the shuttles ability to service it, Hubble would have been a huge flop rather than providing some of mankind's best views of the universe. Well done to NASA for allowing this last servicing mission to go ahead, and best of luck to the crew in their task.
No piss recycler
It was only after getting to the end without reading anything about a piss recycler that I realised it was Hubble rather than the ISS.
A golden watercooler for Hubble say I!

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