(AFP) — Millions of pieces of man-made debris are currently orbiting the earth.
This huge cloud of space junk is suspended between 800 and 2,000 kilometers above us.
Since space exploration began in 1957, fragments from more than 5,000 space launches and 290 orbital explosions have been accumulating.
Old rockets, satellites, tools lost by astronauts and even flecks of paint pose a serious threat to future space exploration, particularly manned flights and stations.
Sensors carried on space vehicles only tend to detect micro-debris but damage from a collision can be serious due to the very fast orbital speed of this debris, travelling at some 28,000 kilometers an hour.
The International Space Station for example has had to perform avoidance maneuvers more than a dozen times.
There is also the risk of debris slamming into the hundreds of earth observation and telecommunication satellites which orbit the earth.
Billions of dollars’ worth of weather monitoring equipment, global navigation and communications systems are at risk.
The big fear is of a collision occurring and triggering a chain reaction, known as the Kessler syndrome.
Thousands of pieces of debris measuring more than 10 centimeters and sometimes as big as a bus, are currently being tracked and followed from earth by radars and telescopes.
Space agencies have guidelines in place on how to deal with potential collision threats but as yet, no viable method exists for debris removal.
The 4 billion euro EU-funded STARDUST project – involving NASA and universities around the world – aims to tackle the threat of both space junk and asteroids by developing strategies to deflect or remove space debris.