Two satellites collide at high speed

Two communications satellites collided in the first-ever crash of its kind in orbit, shooting out a pair of massive debris clouds and posing a slight risk to the International Space Station.

NASA said it would take weeks to determine the full magnitude of the collision, which occurred Tuesday nearly 500 miles above Siberia.

“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 space station and its three astronauts is low. The station orbits about 270 miles below the collision course. There also should be no danger for the space shuttle set to launch Feb. 22 with seven astronauts, officials said, but that will be reevaluated.

The collision involved an Iridium commercial satellite launched in 1997 and a Russian satellite launched in 1993 and believed to be nonfunctioning. The Russian satellite was out of control, Matney said.

The Iridium craft weighed 1,235 pounds, and the Russian craft nearly a ton.

No one has any idea yet how many pieces were generated or how big they might be.

“Right now, they’re definitely counting dozens,” Matney said. “I would suspect that they’ll be counting hundreds when the counting is done.”

As for tiny pieces, the count probably will be in the thousands, he said.

Nicholas Johnson, an orbital debris expert at the Johnson Space Center, said the risk of damage is greater for the Hubble Space Telescope and Earth-observing satellites, which are in higher orbit and nearer the debris field.

The incident was the first high-speed collision between two intact spacecraft, NASA said.