755p 12/22 Update: Spacewalk begins

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CBS NEWS Coverage of Breaking Space News
Posted: 7:55 PM, 12/22/08

By William Harwood
CBS News Space Consultant

Changes and additions:

12/21/08 (01:30 PM): Amid uncertainty, NASA prepares for Ares 1-X test flight
12/22/08 (10:45 AM): Station astronauts gear up for spacewalk
12/22/08 (07:55 PM): Spacewalk begins

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7:55 PM, 12/22/08, Update: Spacewalk begins

Running about 40 minutes behind schedule, space station commander Mike Fincke and flight engineer Yury Lonchakov opened the outer hatch of the Pirs airlock module tonight at 7:51 p.m., officially kicking off a planned six-hour 10-minute spacewalk devoted to external experiment servicing and minor maintenance.

The spacewalkers also plan to install an electrical probe on the hull of the Pirs compartment to help characterize the charged plasma environment around the Russian part of the lab as part of an investigation into what caused explosive bolts to fail on two recent Soyuz spacecraft after they left the station. Engineers suspect arcing caused by the lab's interaction with the space environment caused a specific bolt to malfunction, triggering Soyuz module separation problems during re-entry that led to steep, off-course descents.

After the Langmuir probe is installed near the Pirs hatch, Fincke and Lonchakov will install two experiment packages, one devoted to studying disturbances in the ionosphere and the other to exposing biological samples to the space environment for a full year. They also plan to retrieve an experiment package, cut away some errant straps near the Pirs docking port and carry out a few other minor maintenance chores. If time is available, they will take photographs of a rendezvous antenna on a recently docked Progress supply ship that failed to operate properly during final approach.

This is the fifth spacewalk for station-veteran Fincke, the first for Lonchakov and the 19th and final space station excursion planned for 2008. Overall, it is the 119th EVA devoted to station assembly and maintenance since construction began in 1998.

Please see the 10:45 a.m. status report for a detailed spacewalk overview.

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Quick-Launch Web Links:

CBS News STS-119 Status Reports:
http://www.cbsnews.com/network/news/space/current.html

CBS News STS-119 Quick-Look Page:
http://www.cbsnews.com/network/news/space/currentglance.html

NASA ISS Expeditions Page:
http://www.nasa.gov/mission_pages/station/expeditions/index.html

NASA Shuttle Web: http://spaceflight.nasa.gov/shuttle/index.html
NASA Station Web: http://spaceflight.nasa.gov/station/index.html
Spaceflight Now: http://spaceflightnow.com/index.html
GoogleSatTrack: http://www.lizard-tail.com/isana/tracking/

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