After a major leak detected on December 15, the Russian authorities, aided by the Americans, delivered their conclusions on January 11. The three astronauts of the Soyuz MS-22 crew will not return with their capsule, but with Soyuz MS-23, which will take off empty in February.
The mission schedule will be a little more complex than expected.
Jewel, owl, pebble, hole
The final decision was eagerly awaited, but the Roscosmos investigation, conducted in partnership with NASA, took time to study the various possible conclusions. American Francisco Rubio and his two Russian colleagues, Sergei Prokopiev and Dmitri Petelin, have indeed been in an uncomfortable position since December 15, when a major coolant leak was detected on their Soyuz MS-22 capsule docked at the ISS.
Immediately, the investigations started with the teams on the ground to first find the causes of this leak, establish with precision the level of security of the three astronauts and know what decision to take for the months to come.
It’s an accident my dear Watson
Thanks to multiple series of shots (taken with the help of the Canadarm2 robotic arm, operated from the American part), internal Soyuz sensors and interior inspections, Roscosmos concluded that the origin of the leak is external, with a hole about a millimeter in diameter that punctured the radiator and probably one of the fluid hoses. It would therefore not be a design problem, but rather a debris impact or a micrometeorite. A real risk, since small objects (a few centimeters or smaller) are very poorly mapped. Although, given the position and orientation of Soyuz during impact, the affected area was not very exposed. Like what, accidents do not always happen where we expect them.
The result of this leak is clear: the main cooling system of the Soyuz MS-22 orbital module no longer works, since it has no more pressurized liquid. Its on-board systems are working well today, and the Russian and American teams believe that if there is really a life-threatening emergency, it would still be possible for its three occupants to return with them to land in Kazakhstan. However, the situation is not ideal. To avoid a breakdown and remove any risk for the astronauts, Roscosmos decided that MS-22 would return empty. The capsule will take on cargo and return to land on Earth, studying the temperatures on board in particular, to better document this unprecedented breakdown. But the astronauts will return with Soyuz MS-23.
Exchange broken MS-22 against new MS-23 (make offer)
Originally, the MS-23 capsule was to take off from Baikonur in March with a new Russian-American crew, but since an empty vehicle is always needed to be able to repatriate the occupants of the ISS, it will take off empty. , and as soon as possible (the date of February 20 is currently in the calendars).
As Soyuz is able to dock automatically with the station, it will therefore come empty and leave with the three astronauts in due time. To maximize the scientific contribution of the crew, their mission will also be extended by several months. Until September, when MS-23 should have returned to Earth? The agencies haven’t made that clear, though that’s probably the goal. Indeed, it will still be necessary to take into account the health (physical and mental) of Francisco, Sergei and Dmitri who, if they are doing very well today, had not planned to spend a year in the modules at 400 kilometers from Earth.
NASA and Roscosmos, who held a joint conference on January 11, wanted to recall that this survey underlined the good understanding between the teams on the ground and in flight and the priority given to the safety of astronauts. If this is a textbook case, a micrometeorite impact is one of many scenarios for which there is a plan to follow. According to NASA officials, it is also a good opportunity to discuss with SpaceX in particular and discuss more exotic solutions in extreme cases, such as the possibility of transferring Soyuz seats to Crew Dragon.
Source : Ria
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