Washington - Two satellites collided in space hundreds of kilometres above Earth, destroying an Iridium commercial satellite in a crash that may result in disruption of service, the US company said on Wednesday.
The Bethesda, Maryland-based company said it "lost an operational satellite" after it was struck on Tuesday by a spent Russian satellite, in what is being described as the first major collision of its kind in space.
US space agency Nasa reportedly was tracking hundreds of particles of debris from the collision, and said that the orbiting International Space Station (ISS) faced an "elevated" but small risk of being struck.
"While this is an extremely unusual, very low-probability event, the Iridium constellation is uniquely designed to withstand such an event, and the company is taking the necessary steps to replace the lost satellite with one of its in-orbit spare satellites," the company said in a statement.
The privately-held Iridium Satellite, which says its network comprises 66 communication satellites plus in-orbit spares, stressed the accident was not the result of a failure of technology or the company's fault.
"This satellite loss may result in very limited service disruption in the form of brief, occasional outages," it said, adding that the company expects to implement a network solution by Friday, and move one of its in-orbit spares in place to permanently replace the destroyed satellite within 30 days.
According to Space News, the US space agency Nasa issued an alert Tuesday saying Russia's 900-kilogram Cosmos 2251 satellite collided with Iridium's 560-kilogram craft at 16.55 GMT, some 790 kilometres above Siberia.
It said Nasa was tracking two large clouds of debris.
The Washington Post quoted a Nasa memo about the incident, saying officials "have determined that the risk to the space station is elevated, and they estimate the risk to be very small and within acceptable limits."
There is little risk the space station will enter the debris clouds, however, as the ISS is orbiting about 354 kilometres above earth, some 436 kilometres below the collision orbit.
Cosmic collisions of space junk are not unheard of, but Nasa officials said it was the first involving a pair of intact satellites, the Post reported.
Nasa spokesperson John Yembrick said the collision debris would continue to spread and could end up forcing the space station into evasive manoeuvres.
"The space station does have the capability of doing a debris-avoidance manoeuvre if necessary," and has done so on eight occasions, he said.
Some 6 000 satellites have been sent into space since the Soviet Union launched the first man-made orbiter, Sputnik 1, in 1957.
About 3 000 satellites remain in operation, according to Nasa.
Nasa's space shuttle Discovery is scheduled to launch from Florida's Kennedy Space Centre on February 22 at the earliest, on a mission to the ISS.