US astronauts had to take shelter after a Russian satellite broke into over 100 pieces near the ISS

• US astronauts took shelter on the ISS after a Russian satellite broke up nearby, NASA said.
• The satellite, RESURS-P1, was decommissioned in 2021 and recently created over 100 pieces of debris.
• Space agencies have been trying to reduce space junk like this from decommissioned assets.

US astronauts on the International Space Station were told to take shelter for about an hour after a Russian satellite broke up nearby, according to authorities.

The National Aeronautics and Space Administration said on Thursday evening that American crews took cover in their spacecraft at about 9 p.m. Eastern Time due to the satellite break-up.

That's about 1 a.m. for the astronauts, who follow UTC time on the ISS.

NASA said its instructions were a "precautionary measure" and that crews were told an hour later they could resume their normal activities.

Meanwhile, US Space Command said the destroyed satellite was the Russian-owned RESURS-P1 decommissioned in 2021.

The satellite's collapse on Wednesday at about 4 p.m. UTC created "over 100 pieces of trackable debris," Space Command added.

"USSPACECOM has observed no immediate threats and is continuing to conduct routine conjunction assessments to support the safety and sustainability of the space domain," its statement said.

LeoLabs, a company that tracks space movements, wrote on X that it was tracking over 180 fragments drifting in orbit after the break.

"We expect this number to increase in the coming days. We are actively analyzing the debris cloud to characterize it, identify a potential cause, and estimate the impact," the firm wrote.

By LeoLabs' estimation, the RESURS-P1 was about 13,200 pounds and held a "nearly circular orbit" when it split.

The Russian satellite was an observation tool capturing high-resolution images that allowed the viewer to distinguish objects on Earth about 1 meter apart.

Russia's space agency, Roscosmos, said in January 2022 that the satellite had been inactive since late 2021 due to the failure of its onboard equipment after operating 3.5 years longer than expected.

Satellite breakups in low Earth orbit can often pose hazards to other satellites, spacecraft, or space stations because of the debris they release.

Debris can sometimes stay for decades in close orbit before Earth's gravity pulls it into the atmosphere and burns it up.

Space agencies have been working to reduce space junk in low Earth orbit as more satellites are decommissioned, primarily because the resulting debris raises the risk of spacecraft crashes.

In October 2023, for example, the Dish Network was fined $150,000 for leaving a retired satellite in the wrong place.

The preferred way of disposing of a retired satellite is typically to send it further away from Earth, reducing the risk of interrupting space activities near the planet. Another way is to allow the satellite to fall into the atmosphere, where it will be burned.