Where did all Space Debris come from?
Space debris consists of natural
(meteoroid) and artificial (man-made) particles. Meteoroids are in
orbit about the sun, while most artificial debris is in orbit
about the Earth.
Orbital debris is any man-made object in orbit about the Earth
which no longer serves a useful function. Such debris includes
nonfunctional spacecraft, abandoned launch vehicle stages,
mission-related debris and fragmentation debris.
There are more than 20,000 pieces of debris larger than a softball
orbiting the Earth. They travel at speeds up to 17,500 mph, fast
enough for a relatively small piece of orbital debris to damage a
satellite or a spacecraft. There are 500,000 pieces of debris the
size of a marble or larger. There are many millions of pieces of
debris that are so small they canít be tracked.
Today, telescopes and radar are
monitoring more than 12,000 pieces of junk down to 10 cm in size.
Many millions of pieces are too small to be recorded, such as
flecks of paint and dust.
Even tiny paint flecks can damage a spacecraft when traveling at
these velocities. In fact a number of space shuttle windows have
been replaced because of damage caused by material that was
analyzed and shown to be paint flecks.
In 1958 the United States launched Vanguard I. It became one of
the longest surviving pieces of space junk. As of January 2012
remains the oldest piece of junk still in orbit.
In 1996, a French satellite was hit and damaged by debris from a
French rocket that had exploded a decade earlier.
On 10 February, 2009, a defunct Russian satellite collided with
and destroyed a functioning U.S. Iridium commercial satellite. The
collision added more than 2,000 pieces of trackable debris to the
inventory of space junk.
China's 2007 anti-satellite test, which used a missile to destroy
an old weather satellite, added more than 3,000 pieces to the
ISS adjusts orbit to avoid Space Debris
The International Space Station moved into a slightly higher orbit
on Friday 13, January, 2012 to avoid a close call with debris from
a 2009 satellite collision. Thusters on the ISS's Zvezda module
fired for nearly a minute at 11:10 am EST (1610 GMT) Friday,
raising the station's orbit by 305 meters. The maneuver was
approved after the US Strategic Command detected a piece of debris
about 10 centimeters in diameter projected to come as close as one
kilometer to the station. The debris was a fragment of the Iridium
33 satellite, which collided with a defunct Russian satellite in
2009. The maneuver was the 13th debris avoidance maneuver in the