A space collision involving a commercial Iridium communications satellite and a defunct Russian satellite collided on Tuesday above Siberia, creating a large cloud of debris. NASA officials have stated that they do not believe the International Space Station is at risk of the flying debris, but it would take more time to determine what if any, other objects are at risk of the flying wreckage.
The Iridium satellite constellation is a system of 66 active communication satellites with spares in orbit and on the ground. It allows worldwide voice and data communications using handheld satellite phones.
The Iridium network is unique in that it covers the whole earth, including poles, oceans, and airways. The satellites are frequently visible in the night sky as satellite flares, a phenomenon typically observed as short-lived bright flashes of light.
“They collided at an altitude of 790 kilometers (491 miles) over northern Siberia Tuesday about noon Washington time. The U.S. space surveillance network detected a large number of debris from both objects,”
said Nicholas Johnson, NASA’s chief scientist for orbital debris at the Johnson Space Center in Houston.
Many Debris Fragments
According to STRATCOM, the U.S. based department that tracks about 18,000 objects in space from satellites to debris, said that they’ve identified over 600 pieces from the wreckage. STRATCOM tracks any objects in space that are larger than 3.9 inches.
“It’s going to take a while” to get an accurate count of the debris fragments, Johnson said. “It’s very, very difficult to discriminate all those objects when they’re really close together. And so, over the next couple of days, we’ll have a much better understanding.”
The two satellites ran into each other, and while it is highly improbable – it happens and it’s neither of the satellites’ fault. The satellites have no way of knowing what is coming at them.
“Yesterday, Iridium Satellite LLC lost an operational satellite. According to information shared with the company by various U.S. government organizations that monitor satellites and other space objects (such as debris), it appears that the satellite loss is the result of a collision with a non-operational Russian satellite,”
the company said in a statement.
“Although this event has minimal impact on Iridium’s service, the company is taking immediate action to address the loss. The Iridium constellation is healthy, and this event is not the result of a failure on the part of Iridium or its technology. 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.”
Iridium Satellite LLC claims to have 285,000 subscribers as of early August 2008 (compared to 203,000 in July 2007). Revenue for the second quarter of 2008 was US$81.7 million with EBITDA of US$25.8 million..
The system is being used extensively by the U.S. Department of Defense through the DoD gateway in Hawaii. The DoD pays $36 million a year for unlimited access for up to 20,000 users.
The commercial gateway in Tempe, Arizona, provides voice, data, and paging services for commercial customers on a global basis. Typical customers include maritime, aviation, government, the petroleum industry, scientists, and frequent world travelers.