In 2004, NASA began to look into the possibility of using a robot to repair the Hubble. NASA would launch the robot using a rocket similar to the ones used in the Apollo missions. Although such a mission wouldn't endanger the lives of humans, there were other considerations that made it a difficult decision. For one thing, engineers designed the Hubble so that humans could make repairs and upgrades, so the robot would have to mimic a human's range of motion in space. For another, such a program would be extremely expensive, making it a challenge to raise the proper funding.
NASA looked at several companies and research facilities when considering a robotic solution to the Hubble problem. Among the candidates was the Canadian Space Agency (CSA). The CSA developed a robot they called Dextre. The robot featured two long, multi-jointed arms that were capable of performing several basic tasks. Early research was promising. But NASA eventually decided against using the robot. Why? Partly because skeptics believed the job of repairing the Hubble was too delicate for a robot. Another big factor was the price -- estimates on the cost of a mission using Dextre ranged between $1 and $2 billion. NASA didn't have enough money in the budget to fund such an operation.
It looked as if NASA was going to let the Hubble die after all. But when Mike Griffin became the NASA Administrator in 2005, he decided to take another look at repairing the Hubble. After some consideration, Griffin announced on Oct. 31, 2006, that a new manned mission would travel to the Hubble to install upgrades and repair the telescope. The proposed changes would extend Hubble's life to 2013. By then, the James Webb Space Telescope should be online and in orbit.
Griffin's announcement meant that NASA again had to take a close look at the space shuttle program. NASA scheduled the repair mission for the summer of 2008. That was first pushed back to the fall of 2008 due to a delay in space shuttle fuel tank production [source: New Scientist]. Further problems delayed the launch until May 11, 2009. Now the space shuttle Atlantis is carrying a crew of astronauts to the Hubble. Standing by is a second space shuttle, the Endeavour. It's the crew of the Endeavour's job to serve as a rescue team if something should go wrong with the Atlantis.
Once at the Hubble, the astronauts will switch out the gyroscopes and batteries, effectively giving the telescope at least five more years of operational power and guidance. They'll also repair some thermal shielding on the telescope designed to protect the Hubble's electronics from the hazards of space. They'll replace the two defective ACS cameras and the STIS, and they'll also install new equipment that gives the Hubble even more capabilities. NASA expects the entire mission will require at least five spacewalks [source: HubbleSite]. All the repairs and upgrades will be done by hand.
Once the Hubble is repaired, what happens then? Find out in the next section.