posted 02-24-2015 10:37 PM               

Spacewalks to continue laying cable, grease robotic arm for installation of new docking ports

Expedition 42 commander Butch Wilmore and flight engineer Terry Virts on Wednesday (Feb. 25) will embark on a spacewalk to continue the work they began on Saturday to prepare the International Space Station for a pair of new international docking adapters (IDAs).

On this, the second of their three planned spacewalks together, the duo will continue routing cables and ready the Canadarm2 for the installation of the IDAs, which will enable future U.S. commercial crew vehicles to connect with the orbiting outpost.

Wednesday's spacewalk is scheduled begin at 6:10 a.m. CST (1210 GMT) and run about 6.5 hours.

posted 02-25-2015 07:24 AM               

Wilmore, Virts begin their second spacewalk

Barry "Butch" Wilmore and Terry Virts switched their extravehicular mobility unit (EMU) spacesuits from external power to battery at 6:51 a.m. CST (1251 GMT) on Wednesday (Feb. 25), marking the start of their planned six-hour, 30-minute spacewalk.

Wilmore and Virts will finish routing a series of power and data cables to the port and starboard sides of Pressurized Mating Adapter-2 at the forward end of the Harmony Node 2 module where the first of two International Docking Adapters will be installed later this year.

Virts will also lubricate elements at the latching end of the station's Canadarm2 robotic arm while Wilmore prepares the Tranquility Node 3 module for the relocation of the Permanent Multipurpose Module and the arrival of the Bigelow Expandable Activity Module (BEAM) later this year.

Wilmore, designated as EV1, is wearing a spacesuit with red stripes. Virts is wearing a spacesuit with no stripes and is designated EV2.

posted 02-25-2015 01:02 PM               

Second of three cable-routing EVAs ends

Expedition 42 commander Butch Wilmore and flight engineer Terry Virts are back inside the International Space Station following their successful six hour, 43 minute spacewalk. The second of the pairs' three scheduled outings together ended at 12:34 p.m. CST (1834 GMT) on Wednesday (Feb. 25).

During the spacewalk, Wilmore and Virts completed all the work set out for them, routing cables as part of a reconfiguration of the space station to enable commercial crew spacecraft to dock in the coming years.

Virts also lubricated elements at the latching end of the space station's robotic arm while Wilmore prepared Node 3 "Tranquility" for the relocation of the Permanent Multipurpose Module and the arrival of the Bigelow Expandable Activity Module (BEAM) later this year.

After the spacewalk ended and the two astronauts were safely back inside the airlock, Virts reported detecting dampness in his helmet absorption pad, a precaution added to the suit after a 2013 EVA when ESA astronaut Luca Parmitano's helmet filled with water. Video sent down of Virts still inside his suit showed a "blob" of about 3-inches of water inside his helmet. Despite the water, Virts was never in danger.

This was Wilmore's third career spacewalk and Virts second. It was the 186th EVA in support of station assembly and maintenance.

The two are scheduled to venture outside the space station again on Sunday, March 1.

posted 02-26-2015 08:48 AM               

NASA astronaut and spacewalker Terry Virts reported seeing a small amount of water floating free in his helmet during airlock repressurization at the conclusion of Wednesday's spacewalk. There was no report of water during the spacewalk itself, and the crew was never in any danger.

posted 02-26-2015 08:50 AM               

Ground teams are currently analyzing the situation to confirm the source of the water.

Virts was wearing spacesuit #3005, which experienced a similar issue after a spacewalk in December 2013.

The teams will carefully evaluate the spacesuit data and perform a detailed assessment prior to the next spacewalk. Virts and fellow spacewalker Barry Wilmore are scheduled to perform their third and final spacewalk on Sunday, March 1.

posted 03-01-2015 05:25 AM               

Spacewalk specialists reported that Virts' suit — serial number 3005 — has a history of what is called "sublimator water carryover," a small amount of residual water in the sublimator cooling component that can condense once the environment around the suit is repressurized following its exposure to vacuum during a spacewalk, resulting in a tiny amount of water pushing into the helmet.

A high degree of confidence was expressed that the suit's systems are all in good shape and approval was given to proceed with the third spacewalk in this series of EVAs.