Those pieces of junk are unsafe enough on their own - but they can also generate thousands more smaller pieces of debris if they collide, creating even more risk to the space station and satellites orbiting the Earth. Japan's space agency sent the electrodynamic tether into space along with supplies for the International Space Station. This vessel which is dubbed as "Kounotori" (means Stork in Japanese) and is to blast off from the Southern Island of Tanegashima at around 10:30 pm (IST Local Time or 1330 GMT), attached to an H- IIB Rocket. They are expecting to remove tonnes of junk, including parts of rocket and pieces of equipment from old satellites. This spacecraft has a large magnetic tether which is made from thin wires of stainless steel and aluminium. So the key idea behind its to attach debris to the end of the strip. Scientists say the detritus will be pulled into a lower orbit by the electricity generated by the tether, where it will enter Earth's atmosphere, burning to ash in the process. The orbiting belt of debris has been variously called a "critical contemporary crisis", a "growing threat to space exploration", and a "significant threat to the health and mission success of satellites-and therefore the capabilities they provide..." The aim is to collect debris which is big enough to cause damage to equipment which is up in space and working. It was designed by JAXA engineers with the help of researchers from Nitto Seimo Co., a Japanese fishing net company.
JAXA company engineer Katsuya Suzuki detailed, "The tether uses our fishnet plaiting technology, but it was really tough to intertwine the very thin materials..."
Space junk can zip around Earth at speeds as high as 17,500 miles per hour, and that's risky for the stuff in orbit we still use.
Scientists at JAXA have spent 10 years developing a tether system to pull space junk out of orbit around Earth.
The cargo ship launched Friday is also carrying other materials for the ISS including batteries and drinking water for the astronauts living there.
He added "if we do it successfully in this trial then the next step will be another Test attached to one tip of the tether to one of the targeted object".
Another spokesman for the space agency has said it hopes to put the junk collection system into more regular use by the middle of the next decade.