Astronauts embark on spacewalk to prepare new parking spot at station

CAPE CANAVERAL, Fla. - Spacewalking astronauts prepped the International Space Station on Friday for a new parking spot reserved for commercial crew capsules.

The spacewalk by France's Thomas Pesquet, 39, and American Shane Kimbrough, 49, officially began at 7:24 am (1124 GMT) when the duo switched their spacesuits to internal battery power.

Their main job 250 miles up involves disconnecting an old docking port.

The first spacewalk will prepare the Pressurised Mating Adapter-3 (PMA-3) for installation of the second International Docking Adapter, which will accommodate commercial crew vehicle dockings, NASA said.

The structure, to be moved from the port side of the Tranquility module to the space-facing side of the Harmony module, will become home for the second docking adapter, which will be delivered on a future flight of a SpaceX Dragon cargo spacecraft.

On Sunday, flight controllers in Houston, Texas, will move the old port to provide better clearance for new ships. Pesquet, who is also a flight engineer was busy the entire spacewalk, while Kimbrough, commander of the station's Expedition 50 crew, had more time to spare.

NASA wants to cram in two or three spacewalks before Kimbrough returns to Earth on April 10.

Whitson and Pesquet will take on a third spacewalk to replace an avionics box on the station's truss.

Friday's spacewalk is the second of Pesquet's career, and the fifth for Kimbrough. After taking the foot restraint, he headed to the P1 truss, to look into a suspected ammonia leak, located in a radiator valve in the cooling system.

NASA astronauts are strolling through the untamed vacuum of space to retrofit the International Space Station.

In the next spacewalk, Kimbrough will be joined by NASA astronaut Peggy Whitson.

"We've been tracking a small rate of leakage from that ammonia system over the previous year or so, and our external robotics systems have determined a most likely location where the system may be leaking", NASA Flight Director Emily Nelson said at the news conference. Just to be sure, he carried a high-definition GoPro camera to capture footage for ground crews to investigate the scene more closely.

After the leak inspection, Pesquet planned to lubricate a capture mechanism in a robot arm capture fixture, using a custom tool to reach up into the grapple mechanism to apply grease to critical components.

Before a third spacewalk can be conducted, however, Orbital ATK needs to launch a cargo ship to the space station with replacement parts. That shipment was supposed to be there by now, but repeatedly has been delayed because of rocket concerns.

  • Carolyn Briggs