Three crew members of the international space station had a close call with space junk on Thursday and were forced to take shelter in the Russian Soyuz capsule.
The space debris, which was about the size of a bullet, and moving 20 times as fast, passed within 3 miles of the station early Thursday afternoon ET, NASA said.
Initially, the debris was classified as posing a low threat of collision with the space station. But the possibility was upgraded to a more dangerous red threat on Thursday morning.
The astronauts briefly took refuge inside a Russian escape capsule before returning inside the space station.
Officials said the decision to move the astronauts had been a precaution and that the probability of an impact with the ISS had been low.
If, however, the space junk had struck the station, it could have caused rapid decompression.
The crew have returned to the station. They are in absolutely no danger and the debris has already passed by the station, a spokesman for Russia's mission control said after the incident.
They didn't even close the hatch between the station and the Soyuz.
It is unclear how many times crew members had been told to enter the Soyuz, but officials said this was not the first occasion. Flight controllers have moved the ISS eight times over the past ten years in order to avoid space debris.