STATUS REPORT : STS-125-12

5 a.m. CDT Sunday, May 17, 2009
Mission Control Center, Houston, Texas

05.17.09 STATUS REPORT : STS-125-12

STS-125 MCC Status Report #12

The crew of Atlantis is preparing for the fourth spacewalk of the mission, which will begin today at 8:16 a.m. CDT. The crew awoke at 4:31 a.m. to “New York State of Mind” performed by Billy Joel. The song was played for Mission Specialist Mike Massimino.

Massimino and Mission Specialist Mike Good will focus on repairing the Space Telescope Imaging Spectrograph (STIS) today. STIS was installed on the Hubble Space Telescope during the second servicing mission in 1997. STIS stopped functioning in August 2004 due to a power supply failure and is currently in a “safe mode.”

Just like on the Advanced Camera for Surveys (ACS), Good and Massimino will overlay a fastener capture plate over the top of an access panel on the STIS. But this time, the astronauts will have to loosen 111 screws in order to remove the panel. Once repaired, the STIS will work in tandem with the Cosmic Origins Spectrograph by allowing Hubble to see a full range spectrum. Each of the instruments will back each other up while offering unique capabilities to study black holes, stars and planets around other stars.

Massimino and Good also will install a New Outer Blanket Layer (NOBL) on the outside of bay 8 on the telescope. This is a stainless steel cover that protects the telescope from the extreme environment of space by providing thermal protection for the equipment bays. The existing insulation has degraded over time.

The crew’s sleep period will begin at 8:31 p.m., and the crew is due to wake up tomorrow at 4:31 a.m. and will conduct the fifth and final spacewalk of the mission. The next status report will be issued at the end of the crew’s day, or earlier if events warrant.