A leaking Soyuz capsule on the International Space Station tested its thrusters on Friday (December 16) as Russian engineers investigated why it suffered an uncontrolled coolant leak this week.
The Russian-built Soyuz spacecraft, dubbed Soyuz MS-22, caused a coolant leak on Wednesday evening (December 14) as two cosmonauts prepared for a spacewalk outside the station. Russia’s space agency Roskosmos has canceled that spacewalk and indefinitely postponed another as it investigates the cause of the coolant leak that sprayed coolant particles into space from an external conduit on the capsule. On Friday, NASA also postponed a scheduled US spacewalk to Dec. 21, a two-day lapse, as Soyuz work continues.
Russian engineers ordered the Soyuz MS-22 to fire its engines at 3:08 a.m. EST (0808 GMT) Friday as part of their investigation. The leak was traced to an external coolant loop on the Soyuz spacecraft, NASA said.
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“The systems tested were nominal, and Roscosmos evaluations of other Soyuz systems continue,” NASA wrote in an update (opens in new tab) Friday. “Temperatures and humidity in the Soyuz spacecraft that remains docked with the Rassvet module are within acceptable limits.”
Earlier in the day a Roscosmos update on Telegram (opens in new tab) stated that temperatures inside the Soyuz reached 30 degrees Celsius and were within operational limits, according to a Google translation from Russian. “This is a slight change in temperature,” Roscosmos wrote in the statement, according to the translation.
The Soyuz MS-22 is docked at a Russian port on the earth-facing side of the station. It launched to the station in September to carry Russian cosmonauts Sergey Prokopyev and Dmitri Petelin and NASA astronaut Frank Rubio to the orbiting laboratory. It was Prokopyev and Petelin planning a spacewalk when the leak began Wednesday night. Most of the coolant had leaked by midday on Thursday (December 15), NASA said.
Russian engineers are working to determine the condition of the Soyuz spacecraft, but whether it can still be used to return its crew to Earth as planned in 2023 is unclear.
Roscosmos has deployed a European-built robotic arm to the station’s Russian Nauka laboratory module to inspect the Soyuz capsule and has reported some signs of damage. NASA, meanwhile, will use the station’s Canadian-built Canadarm2 to inspect the Soyuz on Sunday (December 18).