Russia will send an empty replacement Soyuz capsule to the ISS next month to retrieve the two cosmonauts and an astronaut who are now stranded there. The replacement capsule is needed because the original Soyuz capsule has a leak.
The Soyuz MS-23 will be launched on February 20 to replace the current MS-22 capsule, says the Russian space agency Roscosmos according to Reuters. That MS-22 is then sent back to Earth empty.
At the end of last year, it turned out that there was a leak in the Soyuz spacecraft, which was probably caused by a small meteorite less than 1mm wide. That leak was in an external cooling system of the MS-22 and allowed cooling material to escape. During the return flight, the temperatures in the capsule can rise to 30 to 40 degrees Celsius. For that reason, Roscosmos and NASA do not want to use the capsule for the return flight. The organizations do not rule out using the MS-22 in case of emergency. Due to the leak, no spacewalks have been performed in recent weeks.
It was already planned that the Soyuz MS-23 capsule would fly to the ISS, but then in March and with the aim of bringing astronauts to the ISS. The MS-23 is sent empty instead, something Roscosmos already considered. The two cosmonauts and an astronaut who originally planned to return to Earth on MS-22 will now do so on MS-23. As a result, they stay on the ISS ‘a few’ months longer; initially they should have returned to Earth in March. The astronauts in question, Sergei Prokopyev, Dmitry Petelin and Frank Rubio, have been on the ISS since September.