It is no great exaggeration to say that we live in a golden age of astronomy and much of that luster has been provided by the Hubble Space Telescope.
Hubble overcame an awkward start to its career — it was launched with a faulty mirror — but went on to provide heretofore unobtainable measurements about the size, speed and age of the universe and, in image after image — viewable at hubblesite.org — a sheer beauty that is indeed unworldly. But the Hubble was launched in 1990 and despite shuttle-mission upgrades its batteries and gyros are deteriorating and the end of its useful life is in sight, before the end of the decade and before its replacement can be launched.
In the wake of the 2003 Columbia disaster and unwilling to risk the lives of more astronauts, NASA nixed another shuttle repair mission. The shuttle fleet itself was aging, it was argued. The remaining craft were needed to service the space station, a place of refuge if a shuttle became disabled in space, while the Hubble was out of reach of rescue.
Tuesday, after what seems a comprehensive review of the risks, NASA reversed itself and, tentatively in May 2008, Discovery will blast off to install the gear that will extend the life of the Hubble to 2013 and add instruments that will greatly increase what it can see and measure.
In part, NASA’s new confidence in the repair mission is because of the experience that astronauts have gained making complex in-flight repairs to the shuttle.
The safety of the astronauts is paramount but the whole point of manned spaceflight is exploration and the Hubble has been one of our greatest tools of exploration. It is truly worth saving.