On (or maybe before) Tuesday, February 10,  somebody was asleep at the U.S.  Strategic Command (STRATCOM) in Omaha, or  the orbital debris monitoring office at the Johnson Space Center in Houston.

On that day,  a commercial Iridium communications satellite and a now defunct Russian satellite slammed into each other above northern Siberia.  A cloud of wreckage was created.

OK, why is this important?  The Earth is surrounded by a cloud of satellites, the International Space Station (ISS) and junk and debris of all shapes and sizes.  STRATCOM routinely tracks about 18,000 objects near the Earth, including satellites and debris, that are 3.9 inches across or larger.

Why track this space junk? Three reasons:

• Any piece could be an actual weapon;
• It could collide with the ISS, a Space Shuttle, or critical civilian or military satellite, or an astronaut on a space walk;
• It could fall to earth and cause damage without notice.

Approximately 600 new pieces of debris were added to the cloud that blankets the Earth due to this collision.  As for the threat posed by the debris, NASA carried out an immediate analysis to determine whether the ISS faced any increased risk. The station, carrying three crew members, orbits the Earth at an altitude of about 220 miles. There is no immediate threat, but some debris was propelled by the collision up to the ISS's orbital altitude and even higher.  Much more analysis will be needed to find and track these new hazards in the croweded skies surrounding Earth.

Iridium satellites are US communications satellites that frequently cause so-called "Iridium flares" - brief flashes of light in the night sky that are easily mistaken for meteorites.  Amateur astronomers enjoy tracking these 66 (oops - now 65) satellites and predicting when a flare may occur in their local night skies.