Two astronauts are venturing outside the International Space Station to fix a busted antenna

Central Florida Public Media | By Brendan Byrne

Published November 30, 2021 at 7:18 AM EST

Astronaut Tom Marshburn, STS-127 mission specialist, participates in his first spacewalk and the second overall for the crew members of the Space Shuttle Endeavour and the International Space Station, July 20, 2009. Photo: NASA

Two NASA astronauts are stepping outside the International Space Station today to fix a broken antenna. NASA’s Thomas Marshburn and Kayla Barron will exit the airlock Tuesday around 7:10 a.m. EST in their extravehicular activity (EVA) suits to replace an antenna that no longer works.

The antenna transmits radio waves down to Earth using a system of NASA satellites that relay the signal to flight controllers. This particular antenna system transmits low-rate voice and data over the S-band of radio frequencies. NASA says the broken antenna isn’t affecting station operations, but wants to have a backup working just in case.

It recently lost its ability to talk to that system, known as NASA’s Tracking and Data Relay Satellite System, or TDRS. The station is equipped with other antennas, including low-rate S-band systems and a high-rate KU-band communication system that can also beam back video.

For the spacewalk Tuesday, Marshburn will be on the end of the Canadarm2 robotic arm which will be controlled by European Space Agency astronaut Matthias Maurer from inside the space station.

It will be Marshburn’s fifth spacewalk and Barron’s first. They arrived at the station earlier this month with two others, riding in SpaceX’s Crew Dragon capsule that launched on a Falcon 9 rocket from Kennedy Space Center in Florida.

The spacewalk is expected to last about six and a half hours and take place at the Port 1 truss structure, which was first installed to the station back in 2002.

This spacewalk marks the 245th EVA supporting the International Space Station’s assembly, maintenance and upgrades.