Loss from the ISS: USA and Russia consider sending a shuttle to recover the astronauts

Since 15 December there has been aunexplained coolant leak from Soyuz spacecraft docked with the International Space Station (ISS), well documented during a NASA TV live stream. The problem is so significant that the US aerospace agency and Roscomos (the Russian space agency) are considering sending another MS-22 Soyuz shuttle to recover the two Russian cosmonauts and the US astronaut who would have return with the damaged one. At the moment the return of Dmitry Petelin, Sergey Prokopyev and Frank Rubio is still scheduled for March 28 next year; if the Soyuz docked to the ISS was no longer considered safe, the replacement one would be sent in February, effectively reducing the duration of the mission on the ISS.

As for the consequences of the loss, there is still no certainty. Former Roscomos cosmonaut Sergei Krikalev, who currently heads Russia’s human spaceflight program, told state news agency TASS on December 16 that the lawsuit it may have been a micrometeorite that struck the spacecraft’s radiator, which is docked with the Russian Rassvet module of the space station. According to rumors reported by the British news agency BBC, however, the impact of a small space stone would have been excluded from subsequent investigations. What is certain is that around 1:45 UTC (Coordinated Universal Time) on December 15, the alarm sensors relating to the Soyuz cooling circuit were suddenly activated, detecting a significant loss of pressure. The command center immediately activated an inspection with cameras installed on the ISS, detecting the impressive leak, as shown in the following video.

The accident has already had a significant impact on the mission, having forced the two Russian cosmonauts Sergey Prokopyev and Dmitri Petelin to cancel a long-planned EVA (acronym for Extra vehicular activity, commonly known as “spacewalk”). However, the loss did not force us to postpone the spacewalk of the two NASA astronauts Josh Cassada and Frank Rubio, regularly held on December 22nd. At the moment both Roscomos and NASA underline that no crew member is in danger, but if the Soyuz shuttle is not considered safe, in case of an emergency on board the ISS there could be serious problems for the astronauts to escape. To date it has never been necessary to evacuate the space station, even if due to some debris in the past the astronauts have transferred in advance to the shuttles, ready to undock and leave in the event of an impact.

Eventually the space agencies could decide to send the astronauts back with a spacecraft deprived of most of its coolant, essential for maintaining the temperature in equilibrium, but at the moment it is an unlikely hypothesis. Further investigations will be conducted to understand the origin of the problem.