Two veteran cosmonauts floated outside the International Space Station Friday to remove an electronics box and install a more powerful replacement as part of an upgrade to improve communications with the Russian segment of the lab complex. Station commander Alexander Misurkin and crewmate Anton Shkaplerov opened the hatch of the Pirs docking and airlock module at 10:35 a.m. EST (GMT-5) to officially kick off a planned six-and-a-half hour excursion near the aft end of the Russian Zvezda module.
"It is Groundhog Day, after all, and as the cosmonauts have emerged from the Pirs docking compartment, ultimately they'll see their shadow ... thus earning six more hours-plus of spacewalk activity," commentator Rob Navias observed from NASA's mission control center in Houston as the spacewalkers floated out of the airlock.
The spacewalk came just 10 days after two NASA spacewalkers, Mark Vande Hei and Scott Tingle, carried out the year's first station EVA, installing a new grapple mechanism on one end of the lab's robot arm. A second spacewalk to complete unfinished arm-related work is planned later this month.
The goal of Friday's excursion was to remove a 60-pound radio receiver used with the Russian Lira communications system's OHA high-gain antenna. The flight plan called for Misurkin and Shkaplerov to disconnect the old receiver, toss it overboard and install a more powerful unit that will eventually permit high-speed communications and telemetry comparable to NASA's Ku-band system.
The original instrumentation unit was to be jettisoned to the aft of the station along a trajectory that assures no chance of a subsequent close encounter with the lab. The box eventually will fall into the atmosphere and burn up.
The cosmonauts planned to carry out one or more lower-priority "get-ahead" tasks, if possible, before re-entering Pirs, closing the hatch and repressurizing the compartment to bring the spacewalk to a close.
This is the 207th spacewalk since station assembly began in 1998, the second so far this year, the fourth for Misurkin and the second for Shkaplerov. Going into Friday's EVA, more than 120 astronauts and cosmonauts had logged 1,285 hours and 49 minutes of spacewalk time, or 53.6 days.