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Russian cargo ship docked at ISS leaks, the agency delays the Soyuz MS-23 launch

Progress MS-21 lost thermal control system fluid; situation looks the same as Soyuz MS-22

Soyuz MS-23 spacecraft at Baikonur Cosmodrome

After the Russian spacecraft Soyuz MS-22 had a leak in the SOTR thermal control system, leading to a major modification of the schedule of Russian manned flights to the international space station, now it was the cargo ship Progress MS-21 which had the same problem, raising doubts about the manufacturing and assembly procedures for these devices, since they are similar and produced by the same manufacturer. The pressure in the SOTR thermal control system of the instrument and engine compartment (PAO) of the Progress MS-21, coupled to the Poisk module, went to zero and all the coolant leaked. The depressurization took place on Saturday, February 11, 2023, and was preceded by the docking of another cargo ship, Progress MS-22, to the Zvezda service module of the Russian segment of the station.

According to Russian space program sources, the leak appeared after 09:40 UTC; the US was asked to observe the Progress MS-21 with the Canadarm 2 robotic arm, although this is inconveniently located; the launch of the Soyuz MS-23 will be postponed, remaining for February 20; the results of the work of the commission formed to study the Soyuz MS-22 case will be considered ; a meeting will be held at Roscosmos today.

The Progress MS-21 is attached to the Russian segment's MIM-2 Poisk compartment.

NASA manifests