Space: the final frontier...of debris. For decades, nations throughout the world, have sent satellites and manned shuttles into space for exploration and research. But during this time, a massive amount of debris has accumulated in low Earth orbit that now poses a serious threat to spacecraft. Made up of items that range from nonworking satellites and old rocket stages to flecks of paint and a glove lost by astronaut Ed White during the first American space walk, space debris is estimated to number in the tens of millions of pieces. The vast majority of space junk is compromised of particles measuring less than one centimeter in diameter. But some items are much larger and could be lethal should they collide with manned spacecraft. So far, little has been done to rectify the issue, and with the European Union, Japan and India planning future manned space missions, the situation is dire.
1978
NASA scientist Donald J. Kessler proposed a scenario in which the density of objects in low Earth orbit is high enough to cause further collisions of objects -- creating a dangerous and possibly irreversible domino effect of wreckage. The "Kessler syndrome" also predicted that, due to the amount of debris in low Earth orbit, space exploration and the use of satellites would eventually be unfeasible. Kessler's research in space debris earned him the position as head of NASA's Orbital Debris Program Office, which has taken the international lead in adopting space debris mitigation measures.
1996
NASA proposed an idea known as Project Orion -- essentially a "space broom" that would clean up waste by firing ground-based lasers at orbiting objects. The laser beams would vaporize surface material on targets, providing enough recoil to drive it into the atmosphere where it would self-immolate. The catch, however, was that such lasers could be seen as weapons threatening other space exploring nations such as Russia and China.
2001
A set of U.S. Government Orbital Debris Mitigation Standard Practices was developed in 1997 and eventually passed in 2001 to control and minimize the debris released during normal space operations. Other objectives included guidelines for post-mission disposal of space structures by three methods: atmospheric re-entry, maneuvering to a storage orbit or direct retrieval of the structure from low Earth orbit.
2006
For the first time, a revised draft of the National Space Policy included statements regarding space waste, stating that "orbital debris poses a risk to continued reliable use of space-based services and operations and the safety of persons and property in space and on Earth." The new draft called for efforts from government and nongovernment entities operating in space, stating something must be done for future generations of space exploration.
February 2009
A communications satellite owned by the U.S. firm Iridium Communications collided with an inactive Russian military satellite, propelling more than 1,000 pieces of debris into low Earth orbit. The U.S. Joint Space Operations Center confirmed the collision, adding that some of the debris created by the encounter was larger in size than a tennis ball and moving at speeds of more than 20,000 mph. Three days later, residents in Kentucky and New Mexico reported hearing several sonic booms caused by the falling debris.
March 2009
The three-man crew of the International Space Station was forced to evacuate to a Russian escape capsule for 11 minutes when a piece of space debris passed within three miles of the station. Most objects in low Earth orbit travel at more than five miles per second, making impacts potentially catastrophic. The incident was one of only a handful of close calls between a piece of debris and a manned spacecraft.
June 2010
It was announced that NASA's Orbital Debris Program Office expects to begin actively working on how to remove debris in orbit. This came on the strength of the latest National Space Policy issued by President Barack Obama, which specifically orders NASA and the U.S. Defense Department to "pursue research and development of technologies and techniques...to mitigate and remove on-orbit debris."
June 2011
Once again, a piece of space debris sped past the International Space Station, forcing the crew of six to take refuge in their "lifeboats" -- two space capsules for use in the event of a crippled station. The object sped past the station at a reported 29,000 mph. At that speed, even the most miniscule of shrapnel would cause destruction of everything in its path. Luckily, the shuttle was in the process of docking at the time and narrowly avoided the speeding debris of death.
September 2011
The National Research Council issued a report, chaired by Kessler himself, explaining that the problem of space debris has passed the "tipping point." The report called on NASA to find more efficient ways to monitor and clean up the space junk. If nothing is done about the problem, there may be no future for space exploration.