Roscosmos Spacewalk 66: Cosmonauts Install Sun Telescope Outside the ISS

Expedition 74 commander Sergey Kud-Sverchkov and flight engineer Sergei Mikaev on Wednesday, conducted a 6-hour, 5-minute spacewalk (1418–2023 UTC) to install the Solntse-Teragerts telescope on the exterior of the Zvezda service module of the International Space Station (ISS). This instrument is designed to observe and collect data on strong solar flares at various frequencies to improve prediction models, with an expected operational lifespan through 2028.

During the extravehicular activity (EVA), the cosmonauts rode at one end of the European Robotic Arm (ERA), a 40-foot-long (11.3-meter) remote manipulator to retrieve a cassette containing semiconducting material produced by the Ekran-M molecular beam epitaxy (MBE) experiment from the Nauka module; this experiment uses gallium arsenide to create ultra-pure films in microgravity.

The cosmonauts ran into some difficulty retrieving the cassette, including losing a pair of pliers and commands sent from the ground failing to move the experiment's interior mechanisms. However, with some workarounds, they were able to collect the sample for its return inside the station.

Before moving on with their other tasks, Kud-Sverchkov and Mikaev took a moment to recognize the 80th anniversary of RKK (RSC) Energia, Roscosmos' design bureau founded in August 1946 and the birthday of St. Petersburg. The spacewalkers held up a card printed with a commemorative logo and posed for photographs.

The crew inspected and secured a Kurs rendezvous antenna on the Progress MS-33 cargo spacecraft, which had failed to deploy during its March launch, and retrieved a Biorisk science container holding bacterial and seed samples before jettisoning used window cleaners.

This was Kud-Sverchkov’s second spacewalk, bringing his total time in the vacuum of space to 12 hours and 11 minutes, while it was Mikaev’s first. This was also the 279th spacewalk in support of the ISS since 1998.