NASA STS-134 Report #09 4:30 p.m. CDT Friday, May 20, 2011

Mission Control Center, Houston, Texas

HOUSTON – Endeavour astronauts completed a 6-hour, 19-minute spacewalk at the International Space Station Friday, retrieving materials experiments and installing another, and installing an antenna.

Mission Specialists Andrew Feustel and Greg Chamitoff also installed a light on a station handcart, set up equipment for adding ammonia to a cooling loop and installed a cover on a rotary joint for solar arrays.

Mission Specialist Mike Fincke served as intravehicular officer, coaching the spacewalkers through their tasks. Astronaut Steve Swanson, himself a veteran of four spacewalks, was in the station flight control room at the Mission Control Center, serving as spacewalk capcom. Endeavour Commander Mark Kelly provided photo and TV coverage.

Feustel and Chamitoff worked first on unhooking power cables and fasteners to retrieve the Materials International Space Station Experiments (MISSE) 7A and 7B from Express Logistics Carrier 2 on the station’s starboard truss. The suitcase-like devices, opened to expose small samples of numerous materials to the harsh conditions of space, were installed during STS-129 in November 2009.

Feustel installed and connected the new MISSE 8 experiment there, while Chamitoff moved on to the light installation on the Crew Equipment Translation Aid (CETA) cart, on truss rails at the S3 segment. Next the two installed a cover on the starboard solar alpha rotary joint. The joint allows solar arrays to rotate to follow the sun.

Working together they installed a jumper cable, and vented nitrogen from another loop. That work was in preparation for adding ammonia to the P6 photovoltaic cooling loop during the next spacewalk, the second of the mission’s four, by Feustel and Fincke. The P6 loop has a slow leak.

For the most lengthy task of the spacewalk, Feustel and Chamitoff moved on to install and connect antennas for the External Wireless Communication System. The antennas are integrated into two replacement handrails. Chamitoff installed them on the U.S. laboratory Destiny while Feustel routed cables. Together the astronauts worked to connect those cables.

An issue with a carbon dioxide level sensor in Chamitoff’s suit caused replanning of the later part of the spacewalk. Removal of a micro meteoroid debris shield to access some cable connection points and to hookup some of the cables was put on hold to ensure Chamitoff would be back in the airlock early.

There was no indication that his suit’s carbon dioxide levels would rise, but without information from the sensor, flight controllers decided on the conservative course of action.

The spacewalk ended at 8:29 a.m. CST, a little earlier than had been planned.

The Friday spacewalk was the fourth for Feustel and the first for Chamitoff. It was the 156th for station assembly and maintenance and the 245th by U.S astronauts.

Pilot Greg Johnson and Mission Specialist Roberto Vittori spent much of the spacewalk period transferring equipment and supplies from Endeavour’s middeck to the station.

The Mission Management Team decided to proceed with a focused inspection of one damage site on Endeavour’s underside Saturday morning. The location is between the right main landing gear door and the External Tank disconnect door.

The shuttle robotic arm will be used to lower the Orbiter Boom Sensor System over the wing and to the underside, to about a seven-foot distance away from the damage site to take three digital camera pictures and two data takes with the laser system.

Meanwhile, the station’s robotic arm will be positioned on the other side of Endeavour with a vantage point looking under, toward the orbiter, to provide camera views for clearance.

The experts will use this data to give them a three-dimensional view that will show what is exposed and its depth to provide a better idea of the dimensions of the cavity and analyze how it will react to reentry.

The rest of Endeavour’s heat shield has been cleared for entry from ascent debris damage.

The next status report will be issued after crew wakeup, or earlier if warranted.