NASA Television
From a The Soyuz spacecraft began to lose coolant uncontrollably on Wednesday night, flight controllers from Roscosmos, NASA and other International Space Station partners have been closely studying the incident data.
Although there is no immediate danger to the seven astronauts aboard the space station, this is one of the most serious incidents in the history of the orbiting laboratory, which has been continuously occupied for nearly a quarter of a century. Among the most pressing questions: Is the Soyuz MS-22 spacecraft safe to fly back to Earth? If not, when can a replacement, Soyuz MS-23, be flown? And if there is an emergency, what are the three crew members scheduled to fly home on MS-22 doing in the meantime?
NASA has not held any briefings since the incident and has released only one pretty bland update on his blog. But there is a lot going on behind the scenes, and this story will try to summarize what is known and what is not known at the moment.
what is known
Roscomos was never able to stop the leak from the external cooling circuit, so the leak only stopped when there was no more refrigerant left. Immediately afterwards, Russian flight controllers attempted to use the European robotic arm, attached to the Russian segment of the station, to observe the aft end of the Soyuz where the leak occurred. This 11-meter arm did not provide conclusive data.
As a result, NASA will use the 17.6-meter-long Canadarm2, also known as the Space Station Remote Manipulation System, to take a closer look at the Soyuz spacecraft. This visual inspection, likely to take place over the weekend, is expected to provide more definitive information about the origin of the leak, its cause and whether other elements of the Soyuz spacecraft were damaged. To facilitate this job, NASA will delay a spacewalk scheduled for Monday by astronauts Frank Rubio and Josh Cassada.
In other diagnostic work, Roscosmos tested the thrusters of the Soyuz MS-22 spacecraft early Friday morning to determine if there was a problem with its propulsion system. This test, according to the sources, was nominal.
The biggest concern, however, is overheating of the flight computers aboard the Soyuz spacecraft. They are used to calculate a precise Soyuz entry to ensure it lands in a designated area of Kazakhstan, close to recovery forces. Without the flight computers, the procedure would have to be done manually. This is possible, but it is far from optimal, since the area in which the Soyuz could land would be very wide.
During the booster test Monday morning, the flight computer warmed up, but did not exceed temperature limits, according to a source. There was a speculative report in the Russian press that the Soyuz MS-22 spacecraft reached an internal temperature of 50 degrees Celsius, but Roscosmos said this is not exact.
