NASA Astronauts on Spacewalk Replace Faulty antenna

NASA astronauts on a spacewalk replaced a faulty antenna outside the International Space Station, restoring one of the ways the orbiting outpost communicates with Earth. Expedition 66 crewmates Tom Marshburn and Kayla Barron completed the 6-hour, 32-minute extravehicular activity (EVA) on Thursday.

They had installed a spare S-band Antenna Subassembly (SASA) on the station’s backbone truss in place of a degraded unit, which was stowed on an exterior pallet. Marshburn and Barron began the spacewalk at 6:15 a.m. EST (1115 GMT), switching their extravehicular mobility unit (EMU) spacesuits to internal battery power shortly before exiting the station’s U.S. Quest airlock.

After gathering up their respective tools, the astronauts then headed to their first planned workstations. While Marshburn retrieved a portable foot restraint to mount to the end of the station’s Canadarm2 robotic arm, Barron made her way to the ExPRESS Logistics Carrier-3, a platform mounted on the Port 1 (P1) truss where the spare antenna was stored.There, Barron worked on temporarily stowing the tools she and Marshburn would need for the replacement and began preparing the spare SASA for its removal from the pallet. Marshburn mounted the end of the 58-foot Canadarm2 to be positioned near the failed SASA. NASA astronaut Raja Chari and Matthias Maurer of the European Space Agency operated the robotic arm’s controls from inside the station to move Marshburn into place.

The SASA is used to transmit low-rate voice and data to and from the ground. In September, the antenna on the P1 truss lost its ability to send signals down to Earth via NASA Tracking and Data Relay Satellite System. Another unit was still functioning, and the space station still had full use of its high-rate KU-band communications system to relay video. Mission managers decided to replace the faulty antenna to preserve redundancy.