NASA Astronauts Repair X-Ray Telescope Outside ISS

This morning, on Thursday, January 16, at 8:01 a.m. ET, two NASA astronauts ventured outside the International Space Station (ISS) for a spacewalk. Their mission, expected to take about six and a half hours, involves repairing the NICER (Neutron star Interior Composition Explorer) X-ray telescope mounted on the station’s exterior.

Nick Hague and Suni Williams are undertaking NASA’s first spacewalk in over six months. Spacewalk activities were paused following a spacesuit leak in June 2024. Fortunately, both astronauts are encountering no suit issues, enabling them to focus on their task of applying special patches to the damaged areas of the telescope’s light filter. These patches will reduce excessive light interference, ensuring more accurate readings from the observatory.

NASA representatives expressed gratitude on social media for Hague and Williams’ efforts in repairing the NICER telescope, an instrument designed to study dense celestial objects known as neutron stars through X-ray observations. NICER has previously created a remarkable map highlighting X-ray sources as observed from the ISS.

Post-repair, NICER will undergo some adjustments and calibrations to ensure it can resume its scientific observations shortly.

The patches for our NICER telescope have been installed thanks to @NASA_Astronauts Nick Hague!

The next steps for the NICER team include unstowing the telescope and restarting daytime observations to examine the data with the patches installed. Stay tuned for updates. pic.twitter.com/JhFgskAmlj

— NASA Universe (@NASAUniverse) January 16, 2025

While conducting their spacewalk, Hague and Williams will also tackle additional tasks, such as removing and replacing a component known as a rate gyro assembly. This assembly is vital for maintaining the station’s orientation as it travels roughly 250 miles above Earth. Other maintenance duties include changing a reflector device on one of the docking adapters, which assists in navigation by indicating the position of the docking area. They will also inspect a section set for future maintenance work.

This upcoming maintenance will involve a future spacewalk to work on the Alpha Magnetic Spectrometer, an instrument designed to explore dark matter that was classified as “unfixable” in 2011. However, astronauts succeeded in repairs in 2023, which included special tools designed to modify its cooling system, extending its operational life despite it originally being intended for only three years of use without astronaut maintenance.

For those interested in watching the spacewalk, it can be viewed here: