NASA made a bittersweet announcment yesterday: they plan to send the space shuttle Discovery to service the Hubble Telescope one last time before the three remaining shuttles are retired. There has been some debate over whether this mission is worth the risk — in the new, ultra-cautious, post-Columbia era, safety protocols demand that the shuttle be able to reach the International Space Station in the event of a damaged heat shield or any other problems; however, orbital mechanics make it impossible for a Hubble-bound shuttle to meet up with the ISS if it had to.
I’ve never been a fan of the new safety protocols, which seemed far too timid in light of the dozens of successful shuttle flights that preceded the Columbia disaster. I’m glad that someone in authority decided to bend the rules this one last time, both because I want to see the Hubble’s lifespan extended — it’s an awesome scientific instrument, and I love the mind-blowing photos it sends back on an almost daily basis — and also because it’s what the shuttle was designed to do, and it ought to be allowed to retire on a high note instead of going out with a whimper. Phil provides the mission details:
The [shuttle astronauts] will install the two science instruments: the Wide Field Camera 3 and the Cosmic Origins Spectrograph, both of which are sitting in a warehouse waiting to go. They’ll replace all six gyros and the batteries. They’ll add thermal insulation blankets on the outside of Hubble. They’ll replace one Fine Guidance Sensor, an incredible telescope that keeps Hubble locked on to its targets (and which can be used for some science). They’ll also install an “over voltage protection device”, and a soft capture mechanism on Hubble’s aft end to facilitate docking. Finally, they will try to fix STIS, the Space Telescope Imaging Spectrograph, which shorted out a few years ago.
This is an extremely ambitious mission, which will require five spacewalks over 11 days; in addition, the Discovery will be carrying the heaviest load ever flown to Hubble, and astronauts will need to remove screws and swap out components that weren’t meant to be handled in orbit. I have no doubt, however, that they’ll be able to do it. NASA missions have never been more spectacular than when the astronauts and ground crews have been forced to improvise a solution. Their efforts will enable Hubble to function until at least 2013.
