Orbital Debris

Looks can be deceiving.  This small window crack occurred in orbit when the space shuttle (STS-007: 1983 Challenger flight) encountered what is believed to have been a flake of paint.  The pitting was disturbingly deep.

On February 10, two large satellites collided over Russia while travelling in orbits almost 90 degrees to each other.  No one knows how much orbital debris was created by the impact but it is assumed there will be hundreds of fragments.  Most much bigger than a flake of paint as each satellite weighed much more than half a ton.

These satellites were in an orbit 750 km high which places them almost 400 km above the International Space Station (ISS).  So, little risk to the ISS.  However, many other satellites are up there and will now be at risk from the hundreds of objects in the debris fields.  If a large piece of debris hits another satellite it will create more debris and could cause a cascade of satellite impacts.

In the past two years both China and the USA have tested their anti-satellite capability by hitting old satellites with a missile.  Again, more debris.  In the latter case I, and my family, actually witnessed the disintegration of the US satellite has it passed over Williams Lake just ten minutes after missile launch.

Photo credit: NASA