Cosmonauts spot coolant leak during spacewalk outside International Space Station
Two cosmonauts conducting a spacewalk outside the International Space Station (ISS) on Wednesday (Oct. 25) got an up-close view of a coolant leak that was first observed flowing from an external radiator earlier this month.
During the extravehicular activity (EVA), Oleg Kononenko and Nikolai Chub, both from the Russian federal space corporation Roscosmos, began by isolating and photographing the radiator, which was first noticed leaking coolant on Oct. 9. The radiator serves as a backup to a main body radiator that regulates the temperature inside Russia’s Nauka multipurpose laboratory module.
Shortly after completing the task, Kononenko noticed a “blob” or “droplet” of pooling ammonia between two panels of the radiator. The cosmonauts had expected to come into contact with the coolant and had prepared with tissues and cloths to prevent any toxic material from entering the space station.
“The holes have very even edges, like they’ve been drilled through,” Kononenko reported to the flight controllers in Moscow Mission Control. “There are lots of them. They are spread in a chaotic manner.”
It is believed that the “blob” formed from the residual ammonia that was disturbed during the process of closing the valves. Russian engineers will analyze the data collected by the cosmonauts to determine the cause of the leak and develop a plan for future use of the radiator.
In addition to investigating the coolant leak, Kononenko and Chub also installed a synthetic radar communications system on the Nauka module. The radar will be used to monitor Earth’s environment and was the first science payload to be mounted on the module’s exterior. However, the panels of the radar only partially deployed, and the cosmonauts’ attempt to fully deploy them was unsuccessful.
Furthermore, the cosmonauts released a nanosatellite designed to test solar sail technology. Developed by a team at the Bauman Moscow State Technical University, the cube-shaped smallsat was meant to demonstrate the deployment of an experimental solar sail. Unfortunately, the solar wings did not extend as planned.
The 7-hour, 41-minute spacewalk concluded with the closure of the hatch to the Poisk module airlock. This EVA marked the first for Chub and the sixth for Kononenko, who has now accumulated a total of 41 hours and 43 minutes working in Orlan spacesuits in the vacuum of space.
Overall, the cosmonauts’ spacewalk provided vital information to resolve the coolant leak issue and contributed to ongoing scientific experiments and technological advancements at the International Space Station.