Scientists are keeping a close eye on orbital debris created when two communications satellites — one American, the other Russian — smashed into each other hundreds of miles above the Earth.

NASA said it will take weeks to determine the full magnitude of the unprecedented crash and whether any other satellites or even the Hubble Space Telescope are threatened.

The collision, which occurred nearly 500 miles over Siberia on Tuesday, was the first high-speed impact between two intact spacecraft, NASA officials said.

“We knew this was going to happen eventually,” said Mark Matney, an orbital debris scientist at Johnson Space Center in Houston.

NASA believes any risk to the international space station and its three astronauts is low. It orbits about 270 miles below the collision course.

ABC News: Scientists Eye Debris After Satellite Collision.