SUBMITTED BY ARTHUR N1ORC - AMSAT A/C #31468

*Astronauts Go to Work Outside Space Station* 3 November 2007

Astronauts are working outside the International Space Station to repair a torn solar array. Mission Specialists Scott Parazynski and Doug Wheelock began the spacewalk, the mission’s fourth, at 6:03 a.m. EDT.

The spacewalk will see Parazynski riding the station’s robotic arm up to the damaged area of the array. He will be secured in a foot restraint on the end of the Orbiter Boom Sensor System, or OBSS – the extension to the shuttle robot arm used for inspection of the orbiter’s thermal protection system.

Though this will be the first operational use of the OBSS to reach a worksite, the task was demonstrated during a spacewalk on the STS-121 mission in July 2006 to prove the boom could provide a stable environment for this type of work.

As Parazynski installs homemade stabilizers and releases the snag suspected of causing the tear in the array panel, Wheelock will assist from the base of the solar array. The distance from the station’s center is about 165 feet out on the truss and approximately 90 feet up to the damaged site.

If all goes as planned, the crew inside will then deploy the array half a bay at a time while Parazynski watches for any new complications. The spacewalk is scheduled to wrap up about 1 p.m.

+ View images from Nov. 2 Mission Status Briefing http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts120/news/msb_sts120_fd11.html

*Mission Information* + STS-120 Mission Overview http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts120/index.html + Harmony Node 2 http://www.nasa.gov/mission_pages/station/behindscenes/harmony_payload.html + Space Shuttle Discovery http://www.nasa.gov/centers/kennedy/shuttleoperations/orbiters/discovery-info.html