Some of the analysis will track the cooling system response during day/night cycles and over changes in solar beta angles on the station’s orbital course.
Prior to the spacewalk, cooling responsibilities for the leaky 2B cooling loop were reassigned to a companion 2A loop. Radiator panels extend from the solar modules to thermally condition external power storage batteries as well as the many life support, science and avionics components laced throughout the station.
Seven channels were deemed sufficient for the scheduled late May 13 departures of three ISS crew members, including Marshburn. He was to join ISS commander Chris Hadfield and cosmonaut Roman Romanenko aboard the Soyuz TMA-07M spacecraft late in the day as they undocked and descended to a parachute-assisted landing in Kazakhstan, ending a 146-day expedition.
A factor in the spacewalk’s urgency was Marshburn’s familiarity with the leak site. During a July 2009 shuttle space station assembly mission, he and Cassidy teamed for a spacewalk at P-6 to replace power storage batteries.