Houston, we have a problem.

Russian aerospace engineers discovered “one more crack” in the International Space Station (ISS) this week, says mission lead Vladimir Solovyov.

“So far, we have found one place and suspect another, whereas some kind of leak exists,” Solovyov said. He described the air loss as “insignificant.”

The ISS typically maintains air pressure of 750 mmHg. The crack is causing the station to lose between 0.3 and 0.4 mmHg per day. They will declare an “emergency” when the pressure starts to drop at 0.5 mmHg per minute.

To learn more, the cosmonauts “must bring a powerful microscope on a cargo spacecraft and use [it] to examine this place,” continues Solovyov. “We are working on it, of course. We understand clearly that these places are at issue. They are indeed not airtight, we understand that there could be some other places, but there is no horror in that, I can say it responsible as the mission head.”

Mission Control Center reported a possible air leak at the station in September 2020. However, it was unclear where the leak was located.

In October, ISS crewman Sergey Ryzhikov reported a jagged scratch in the hull measuring 4.5 centimeters long.

In November, a team photographed the location of the scratch but discovered no damage to the hull. A previous hole, discovered in 2018, turned out to be the result of a poor repair job.

The ISS, launched back in 1998, is a habitable space station and collaborative project involving NASA, Roscosmos (Russia), JAXA (Japan), ESA (Europe), and CSA (Canada).