An unknown piece of space debris was detected near the International Space Station, NASA said yesterday. The station executed an “avoidance maneuver” on Tuesday night to get out of the way of the debris, boosting its orbit around Earth. “At no time was the crew in any danger,” NASA wrote in a blog post.

Thrusters on an uncrewed Progress cargo ship attached to the station were used to boost the station’s orbit, according to NASA. During the maneuver, the astronauts on board the station moved into the Russian segment so that they’d be closer to the Soyuz passenger spacecraft. Once the 150-second-long maneuver was over, the crew went back to their normal activities.

It’s not clear yet what the space debris was, but NASA said that flight controllers in Houston were tracking the object with assistance from US Space Command. At one point, it was expected to come within 1.39 kilometers (0.86 miles) of the station.

The ISS has been hit by bits of small space junk before. It’s also successfully steered clear of more dangerous space debris. In 2015, the station adjusted its orbit to avoid a piece of a Minotaur rocket that had launched two years before. Back then, they also used thrusters of an attached Progress spacecraft to raise the station’s orbit.

The problem of space junk has only become more acute over time. On Twitter, Jim Bridenstine, the head of NASA, said that “Debris is getting worse!” and mentioned that the space station has moved to avoid debris three times in 2020 alone.

As space gets more crowded, with several giant satellite constellations in the works, NASA continues to worry about space junk cluttering low-Earth orbit. As yesterday’s close call showed, a future where space debris can be repaired (or trapped) can’t come soon enough.