NASA and its Russian partner Roscosmos are searching for the cause of the small leak in the International Space Station this weekend, specifically air released slightly more rapidly from the ISS for over the past year. The three crew members currently onboard the station will stay in the Russian segment of the ISS over the weekend, while NASA tries to isolate the origin of the leak in other parts of the spacecraft.

NASA initially noticed the leak on the station which they noticed way back in September of 2019. The air inside the station slowly leaked out of the ISS over time, but officials have come to notice that the air seemed to be leaving at a slightly faster rate than usual. Since then, the leak seems to have somewhat increased. But, NASA hasn’t had much time to investigate. Things have been pretty busy on the ISS since September, with astronauts performing different spacewalks and new vehicles like SpaceX’s Crew Dragon transporting people to and from the ISS. The leak hasn’t been a major issue since tanks onboard the ISS can help maintain the station’s pressure whenever air escapes.

Now that the schedule has slowed down, NASA has time to look for the location of the leak. NASA astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner will bunk together inside the Russian segment after closing all of the hatches to the other ISS modules. Over the weekend, NASA will observe the air pressure levels in each individual module in order to spot the leak. The results of the test should be available next week.