As two cosmonauts prepared to step out in spacesuits on the sides of the International Space Station, a coolant leak broke out outside the Soyuz MS-22 capsule. The crew is doing well and staying safe as they talk to ground crews to assess the problem.
There are many possible options for the sequel.
Outing canceled due to leak
Clearly, Sergei Prokopiev and Dmitri Petelin are not very lucky. Their spacewalk on the ISS, to transfer a radiator from the Rassviet module by a dozen meters to the Nauka module, had already been postponed following problems with one of the spacesuits. Last night, however, all was well for the two crew members, who were already in the airlock and preparing to go out, while Anna Kikina, the third Russian on board the ISS, had the task of piloting the European robotic arm. ERA. A first alarm then caught the attention of ground controllers: a drop in pressure in the cooling circuit of the Soyuz MS-22 capsule. Very quickly, external observations confirm the alert: an external leak evacuates the coolant in a jet which projects tiny drops from the lower part of Soyuz. The scuba ride was first delayed, then canceled.
It’s raining outside…
Inside the International Space Station, the astronauts wasted no time. First to conceal all possible portholes with external protections (including on the objectives of scientific instruments), then to place the station in a particular orientation. Even as S. Prokopiev and D. Petelin terminated operations related to their release, Anna Kikina used the ERA robotic arm to inspect the leak which lasted at least two hours (no more recent images are available). All without panic: there is no immediate danger for the crew or for the station modules themselves. With regard to Soyuz, if the cooling circuit affected by this leak cannot be repaired (which will still have to be specified), there are other circuits which can reduce the impact. Nevertheless, the ground teams, together with the astronauts, have modified the program for the day and are in the process of assessing the situation.
What next for Soyuz MS-22?
Apart from the possible contamination of instruments or scientific experiments because of this leak, the main question remains the state of Soyuz MS-22. The latter must normally remain moored to the ISS until March, after which it will return to land with the Russians Prokopiev and Petelin, as well as the American F. Rubio. But there are several scenarios that could disrupt this agenda. First, you need to know if the system leak is permanent or if it can be repaired. But beware, an exterior repair would be very difficult, especially since Soyuz MS-22 is difficult to access (moored Rassviet, and the leak is at the far end). Then, the Russian teams will meet to find out if the auxiliary systems can compensate for this leak. In theory, yes, but what if the other systems also fail at the worst possible time? If the teams made a concerted decision not to use MS-22 to bring the astronauts back to Earth, then the capsule would be undocked from the ISS and then desorbed, and the takeoff of Soyuz MS-23 (scheduled for March 16) could in turn be advanced. The capsule would take off empty, to be able to bring the “stuck” astronauts back to the ISS.
However, rather than getting lost in guesswork, we must focus on the real situation: part of the ISS’s external operations are on hold to receive as much information as possible… And the ERA robotic arm will be very useful for taking a maximum of shots near the leak but also to find out what could have caused this problem: implosion, overheating, micrometeorite impact? All of this is yet to be determined.
Source: https://spacepolicyonline.com/news/russia-trying-to-determine-source-of-leak-in-soyuz-ms-22-spacecraft-scrubs-spacewalk/
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