Satellites Collide in Earth Orbit!
News story originally written on February 13, 2009

This artwork shows what the Iridium satellite may have looked like shortly before the collision with the Kosmos spacecraft.
Click on image for full size (66 Kb)
Original artwork by Windows to the Universe staff (Randy Russell) using images courtesy of Iridium Satellite LLC and NASA.

On February 10, 2009, two satellites in Earth orbit collided and were destroyed. This was the first major collision between satellites in Earth orbit ever.

The satellites were about 776 km (482 miles) above Siberia when they hit each other. Scientists estimate they were moving at a speed of about 11.6 km per second (26,000 mph) relative to each other when they hit. The collision scattered a huge cloud of debris or "space junk". The debris, moving at very high speeds, is extremely dangerous to other spacecraft and astronauts. Several satellite operators are concerned for the safety of their vehicles. There is some chance the debris might reach the Hubble Space Telescope. NASA thinks the International Space Station is relatively safe because it orbits at a lower altitude (~354 km or 220 miles).

The two spacecraft involved in the collision were an Iridium communications satellite and a Russian Kosmos military satellite. The 950-kilogram (2,094 lb) Kosmos satellite, launched in 1993, had been out of use and essentially "dead" since 1995. The 560-kg (1,235 lb) Iridium satellite, launched in 1997, was operational up until the time of the crash. Iridium's "constellation" of 66 communications satellites includes spares or backups on-orbit; the company is moving one of those to cover the gap created by the destruction of their spacecraft.


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Satellites Collide in Earth Orbit!
News story originally written on February 13, 2009

This picture shows what the Iridium satellite might have looked like just before the Kosmos satellite crashed into it. This is artwork, not a real photo.
Click on image for full size (66 Kb)
Original artwork by Windows to the Universe staff (Randy Russell) using images courtesy of Iridium Satellite LLC and NASA.

In February 2009 two satellites in Earth orbit crashed into each other and were destroyed. This was the first time ever for a major collision between two satellites in Earth orbit.

The satellites were about 776 km (482 miles) above the ground when they hit each other. They were over Siberia at the time. Scientists think they were moving at a speed of about 11.6 km per second (26,000 mph) relative to each other when they hit. The crash scattered a huge cloud of "space junk". The space junk is moving at very high speeds. That makes it very dangerous to other spacecraft and astronauts. Several satellite operators are worried about the safety of their vehicles. There is some chance the pieces might hit the Hubble Space Telescope. NASA thinks the International Space Station is pretty safe because it orbits at a lower altitude.

The two spacecraft that collided were an Iridium communications satellite and a Russian Kosmos military satellite. The Kosmos satellite had a mass of 950-kilograms (2,094 lb). It was launched in 1993, but had been out of use and pretty much "dead" since 1995. The Iridium satellite had a mass of 560 kg (1,235 lb). It was launched in 1997 and was still working up until the time of the crash. Iridium's "constellation" of 66 communications satellites includes spares or backups on-orbit. The company is moving one of those to cover the gap created by the destruction of their spacecraft.


Play the "Junk in Space" Game

Learn More About Space Junk

Space Missions

Satellites Collide in Earth Orbit!
News story originally written on February 13, 2009

This picture shows what the Iridium satellite might have looked like just before the Kosmos satellite crashed into it. This is artwork, not a real photo.
Click on image for full size (66 Kb)
Original artwork by Windows to the Universe staff (Randy Russell) using images courtesy of Iridium Satellite LLC and NASA.

In February 2009 two satellites in Earth orbit crashed into each other. The satellites were smashed into thousands of little pieces. That was the first time ever for a major collision between two satellites in Earth orbit.

The satellites were about 776 km (482 miles) above the ground when they hit each other. Scientists think they hit each other at a speed of about 11.6 km per second (26,000 mph)! The crash scattered a huge cloud of "space junk". The space junk is moving at very high speeds. That makes it very dangerous to other spacecraft and astronauts. Some satellite operators are worried about the safety of their vehicles. There is some chance the pieces might hit the Hubble Space Telescope. NASA thinks the International Space Station is pretty safe because it orbits at a lower altitude.

The two spacecraft that collided were both communications satellites. One was owned by a company called Iridium. The other was a Russian Kosmos military satellite. The Kosmos was launched in 1993, but had been out of use and pretty much "dead" since 1995. The Iridium satellite was launched in 1997 and was still working up until the time of the crash.


Play the "Junk in Space" Game

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Page created February 13, 2009 by Randy Russell.
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