February 12, 2009—Ground controllers in the U.S. and Russia are keeping an eye on what's left of two satellites that apparently crashed into each other high over Siberia, leaving a cloud of wreckage circling the Earth at about six hundred miles per second. Space junk is nothing new at NASA. But, it’s reportedly come close to causing problems before…including one incident during the Cuban missile crisis.

A one ton Russian military satellite called Cosmos 2251 and an American communication satellite called Iridium is little more than pieces the size of your fist. The two reportedly smashed into each other leaving a shower of space junk in Earth orbit. Space junk is anything left over from launches that are under no one’s control. Examples can include anything from spent booster rockets to bolts to flecks of paint. The concern is when debris hits a manned spacecraft, since each object is travelling at around 17,000 miles per hour. No Space Shuttle has been seriously damaged by space junk, but they return from orbit with the windows around the cockpit routinely nicked by something.

Perhaps the worst “close call” of this type was in 1962. The space race was underway, and the Russians launched an unmanned probe to the planet Mars on October 24^th, 1962. The date was eventful since the Cuban missile crisis was at its height. The spacecraft, known simply as 2MV-4, exploded over the North Pole. The blast and the cloud of debris reportedly caught the attention of the Pentagon’s Ballistic Missile Early Warning System, or BMEWS, in Alaska. President John F. Kennedy and Soviet leader Nikita Khruschev were still sparring over Russian missiles in Cuba at the time. Since the world is still here, it’s safe to assume that the explosion was judged an accident, and not an attack.

NASA is watching the debris from the two satellite collision. No threat is expected to the International Space Station. The agency will meet tomorrow to discuss the fuel valve problem on Discovery. Launch is still targeted for February 22^nd, at the earliest.

On the book front, I’ll be at the University of Central Florida’s Life Long Learning Institute on March 3^rd at 11 am to talk about the space program. Some folks at previous talks had their copies of  “Final Countdown” signed. Be glad to do likewise during my upcoming visit.