During a 7-hour-and-20-minute spacewalk today, NASA astronauts gave the Hubble Space Telescope a new backup computer to replace the onboard system that had to be put into use after a technical failure last fall.
The computer, called the Science Instrument Command and Data Handling Unit, is designed to send commands to Hubble's science instruments and also format science data so it can be transmitted to the ground.
The Hubble telescope's main unit failed late last September, leaving the orbiter unable to send data to Earth. Michael Moore, a program executive for the Hubble Space Telescope, has said that the computer problem was the worst the Hubble has suffered since it went into orbit 19 years ago. NASA engineers remotely switched the telescope over to the backup system, and today's spacewalk added another system, which will now serve as Hubble's backup unit.
The space shuttle Atlantis' 11-day mission is focused on repairing and upgrading the telescope, which has not been serviced since 2002. The repairs and additions should make Hubble far more powerful than it's ever been. And that will put Hubble in the position to make more, and more important, discoveries in the next five years than it has in the past two decades, said Ed Ruitberg, deputy program manager for the Hubble Space Telescope.
Today, NASA Mission Specialists John Grunsfeld and Drew Feustel performed the long, grueling spacewalk, which included removing the telescope's Wide Field Planetary Camera 2 and replacing it with a new wide-field camera, which should enable Hubble to take large-scale, detailed photos.
The astronauts, who were aided by astronaut Megan McArthur operating the shuttle's robotic arm, also installed a soft capture mechanism, which will allow future vehicles to attach to the telescope. This is the last space shuttle mission to Hubble, but other space vehicles could someday make another maintenance trip or even go up to retrieve parts of it.
Friday's spacewalk is set up to install six new gyroscopes and three of the six new batteries that will go into the telescope during this mission.