Having suffered only minor damage from its May 11 launch at the Kennedy Space Center, the Space Shuttle Atlantis arrived at the Hubble Space Telescope May 13 to begin the high-risk task of repairing the 19-year-old orbiting observatory. Around midafternoon, NASA Astronaut Megan McArthur captured the Hubble with Atlantis' robotic arm and lowered it into the Atlantis cargo bay.
Once in the cargo bay, the telescope will be latched to a high-tech, lazy-Susan-type device for the duration of the servicing work. An umbilical adjacent to the rotating flight support system will be remotely connected to provide electrical power from Atlantis to the telescope. Then, Atlantis Commander Scott Altman will position the shuttle to allow Hubble's solar arrays to gather energy from the sun to fully charge the telescope's batteries.
And that's the easy part of the mission.
Poised approximately 350 miles above earth and in the middle of heavy space junk traffic, NASA's seven-person crew plans to conduct five spacewalks to install two new instruments, repair inactive ones and perform component replacements over the 11-day mission to keep Hubble operational through at least 2014. The first spacewalk is scheduled for May 14.
Atlantis has already suffered minor debris damage. According to NASA, the liftoff damaged about 25 square feet of the shuttle's launch-pad flame trench and debris from the damage apparently nicked Atlantis. NASA said Atlantis suffered minor dents along an area of about 21 inches spanning four of the shuttle's thermal tiles located on the starboard side of the spacecraft.
Space debris is increasingly threatening space flights. The ISS (International Space Station) and the Space Shuttle Discovery attached to it were forced March 22 to change orbit to avoid being smacked by 10-year-old debris from a Chinese satellite launch. And a breakaway piece of a Russian satellite came close enough to the ISS for NASA engineers March 17 to consider moving the space station and recalibrating Discovery's track to the ISS.
Earlier in 2009, a piece of a Russian spacecraft motor came close enough to the ISS that the three-man crew was forced to evacuate to the Soyuz TMA-13 capsule, which is attached to the space station to transport astronauts back in an emergency.
In addition to the increased risk of being hit by space debris, the repair work and scheduled installations will require a different kind of spacewalk than astronauts encounter at the ISS.
"It's more like brain surgery than construction," explained Lead Flight Director Tony Ceccacci. "On station spacewalks, you're installing large pieces of equipment-trusses, modules, etc.-and putting it together like an erector set. You can't do that with Hubble. Hubble spacewalks are comparable to standing at an operating table, doing very dexterous work."