During the 11-day mission's five spacewalks, astronauts will install two new instruments, repair two inactive ones and perform component replacements. The Science Instrument Command and Data Handling Unit that will be installed in the telescope arrived at Kennedy on Monday. The new unit will replace the one in Hubble that stopped working in September 2008 and delayed the servicing mission.

The result of the upgrades will be six working, complementary science instruments with capabilities beyond those now available and an extended operational lifespan of the telescope through at least 2014.

For those space enthusiasts hungry for additional information about this and other NASA missions, Mr. Massimino and other astronauts are keeping a log of their experiences on sites like Twitter, Facebook, and MySpace. Massimino’s Twitter username is Astro_Mike. These logs provide an in-depth look at the final weeks of preparation for this mission. This is Massimino’s second journey into space.

For NASA TV streaming video, schedules and downlink information, visit:

http://www.nasa.gov/ntv

For the latest information about the STS-125 mission and its crew, visit:

http://www.nasa.gov/shuttle

For more information about the Hubble Space Telescope, visit:

http://www.nasa.gov/hubble