A debris field caused by Russia destroying one of its own satellites with a missile Monday is threatening seven astronauts aboard the International Space Station, U.S. officials say.
Four U.S. astronauts, along with a German astronaut and two Russian cosmonauts, retreated to their docked space capsules on the ISS Monday in case they needed to make an emergency escape, according to NASA. They later resumed normal operations.
The antisatellite missile test by Russia sent thousands of pieces of debris into orbit that U.S. officials said could potentially cause serious damage if they collide with the ISS, which moves at more than 17,000 miles per hour as it circles Earth every 90 minutes.
U.S. government officials strongly condemned the missile launch by Russia, calling it "reckless" and "irresponsible."
"What the Russians did today with these 1,500 pieces of trackable orbital debris poses a risk not only to those astronauts, not only to those cosmonauts, but to satellites, the interests of all nations," State Department spokesperson Ned Price said at a news conference Monday.
Russia on Tuesday confirmed the weapons test but dismissed claims by the U.S. that the debris cloud is threatening astronauts aboard the ISS.
"The U.S. knows for certain that the resulting fragments, in terms of test time and orbital parameters, did not and will not pose a threat to orbital stations, spacecraft and space activities," Russia's Ministry of Defense said in a statement.
NASA astronaut Mark Vande Hei could be heard finding the silver lining of the potentially dangerous situation as he signed off to mission control in Houston on Monday.
"Thanks for a crazy but well-coordinated day," he said. "It was certainly a great way to bond as a crew, starting off our very first workday in space."
Americans Raja Chari, Kayla Barron and Tom Marshburn arrived at the ISS just last week on SpaceX's Crew-3 flight along with German astronaut Matthias Maurer.
U.S. Space Command is now tracking the debris, which could remain in orbit for years. This is the latest instance of space junk threatening the ISS, as a piece of debris caused a small hole in one of the station's robotic arms in June.