Stratfor : A Satellite collision

[andre kesteloot]

 U.S., Russia: A Mysterious Satellite Collision

STRATFOR TODAY » <http://www.stratfor.com/analysis>February 12, 2009 | 
0151 GMT
Rocket carrying Iridium satellites
STR/AFP/Getty Images
A Delta-II rocket carrying Iridium’s first five satellites in 1997

A U.S. Iridium communications satellite and an old Russian 
communications relay satellite collided over Siberia on Feb. 10, 
according to reports that surfaced late Feb. 11. Nicholas Johnson, 
NASA’s chief scientist for orbital debris at the Johnson Space Center in 
Houston, and U.S. Air Force Brig. Gen. Michael Carey, deputy director of 
global operations with U.S. Strategic Command, have both confirmed the 
incident. Iridium Satellite LLC, which provides satellite phone service, 
has released a statement acknowledging the collision.

Multiple sources have now reported the collision. Some 600 pieces of 
debris are already being tracked from the event, which reportedly took 
place over northern Siberia at an altitude of 491 miles. This is well 
within the most popular band of low Earth orbit for satellites. The 
collision appears to have involved the Iridium 33 (NORAD ID 24946) 
communications satellite, launched in 1997, which had been reported by 
Iridium to be operational. The Russian craft was the Cosmos 2251 (NORAD 
ID 22675) communications relay satellite, launched in 1993 and widely 
reported to be nonoperational.

This is the first case in history of two satellites colliding. The 
orbital altitude where the collision took place is among the most 
crowded in low Earth orbit, but statistically speaking, the enormous 
scale of space makes the chance that this kind of direct collision would 
occur completely by accident infinitesimal.

This unlikelihood is compounded by the fact that the U.S. Air Force 
Space Surveillance Network provides space situational awareness and 
tracks some 18,000 satellites, orbital debris and other objects orbiting 
the earth. Though the network’s tracking of each of these objects is not 
constant, all objects of a certain size or larger are catalogued; 
potential collisions or near misses are generally spotted, and 
satellites can usually be maneuvered to avoid them.

As an operational satellite providing regular service, Iridium 33’s 
orbit should have been stable. (Iridium has said that its global service 
has been only minimally affected.) The same is true of Cosmos 2251, even 
though it is likely slowly decaying. Stratfor notes this event first and 
foremost as anomalous — an important part of the intelligence process. 
We will continue to monitor the situation closely.