[UPDATE] Soyuz Spacecraft Has a 0.8mm Hole That Causes the Coolant Leak

A tiny 0.8mm hole was discovered during an assessment of the Russian Soyuz MS-22 spacecraft docked at the International Space Station (ISS).

Coolant leaked last week as two cosmonauts prepared for a spacewalk.

Investigating the Leak

On Wednesday evening, Dec. 14, the Soyuz's coolant began to leak as two cosmonauts prepared to go on a spacewalk outside the orbital outpost, which was later canceled.

According to the report by Space.com, the Russian space agency Roscosmos has been working with its ISS counterparts in the days after the leak to determine the root cause and full extent of the damage.

The Canadarm2, a 17-meter-long Canadian-made robotic arm, was used to help investigate the tethered spacecraft.

With the ISS' sizeable robotic arm, cameras can check the section of the Soyuz where the leak is most likely to have occurred. The investigation concluded on Sunday, Dec. 18, and NASA said on Monday that it yielded some useful information.

In NASA's blog post, released on Monday, it stated, "A small hole was observed, and the surface of the radiator around the hole showed discoloration. Roscosmos is evaluating the imagery to determine if this hole could have resulted from micrometeoroid debris or if it is one of the pre-manufactured radiator vent holes."

One of the most widely accepted theories for the Soyuz leak is that the spacecraft was hit by debris.

As per Ars Technica, there is a worry that the Soyuz spacecraft will overheat if its exterior radiator is not functioning properly.

The delicate flight computers on board might be ruined, requiring a manual descent back to Earth's atmosphere.

The following week's worth of work will likely focus on calculating the spaceship's interior temperature change in preparation for its departure from the space station.

Next Steps

In September, NASA astronaut Frank Rubio and cosmonauts Sergey Prokopyev and Dmitry Petelin boarded the Soyuz designated MS-22 to the International Space Station. In March, it will transport the three back to Earth.

Head of Roscosmos Yury Borisov said that specialized working groups would continue their investigation into the matter for another week. As reported by Ars Technica, it will be decided on what to do next on Dec. 27.

At this time, two potential courses of action are being considered. It is either to send Soyuz MS-22 back to Earth with three crew members aboard or send the next Soyuz in line, Soyuz MS-23, to the station on its own to make the return trip. As early as Feb. 19 next year, this MS-23 might be ready for liftoff.

Russian space authorities have said that if MS-22 is ruled unfit for flight, the next Soyuz will launch from the Russian-controlled Baikonur Cosmodrome in Kazakhstan to bring Prokopyev, Petelin, and Rubio back home.

The Soyuz is one of two spacecraft, along with SpaceX's Crew Dragon capsule, that transport humans to and from the ISS.

However, soon enough, another astronaut taxi will join the existing fleet. In May, an unmanned test flight of Boeing's Starliner capsule traveled to the orbiting lab; in April, the capsule will transport the first crew of astronauts to the station.