So we have littered the streets, rivers, the mountains and now the humans have put junk in outer space also. You must be imagining banana peels or Pepsi cans floating in space. Is that what is defined as space junk or space debris?
Let’s explain, space waste is the collection of unused objects in orbit around Earth. It might be used rocket parts or parts of satellites from disintegration, erosion, and collisions. If their orbits intersect or overlap with new spacecraft, waste may collide with working spacecrafts or satellites. Sometime this space debris crosses in the Earth’s atmosphere and causes damage where ever it falls.
About 10 tonnes of garbage clutters low earth orbits of 2000kms. As long as the pieces of space junk are less than 1 cm, they are not very damaging. They cause erosive damage as they are like dust particles. The ISS has a Whipple shield that protects against such damages.
Recently Russia lost a nano-satellite which was a glass sphere (17cm) in a collision with a piece of weather satellite that was destroyed by a Chinese missile in a 2007 weapon test. Although this space junk might not cause as much damage to us at Earth, it can still damage the satellites and the space crew. The Russian official are really worried about this situation as earlier the chance of collision were once in 5 years, but now it has increased to almost 3 in the same time.
Pieces of debris larger than 5 cm are capable of doing much more damage. However it is the debris over 10 cm (3.9 in) that is extremely dangerous. In order to be safe from such large pieces of junk the spacecrafts have to stay out of their way to avoid collision. If a collision occurs, there might be additional resulting fragments. Any fragments over 1 kg (2.2 lb) can become an additional collision risk. Scientists predict that such collisions will create more junk and trigger a chain reaction once it reaches a critical number of such objects. We have yet to find out if the space junk has reached that number.
How does this affect us? We have come to rely on the geostationary satellites for so much information. All that will be lost in next 20 years because of pollution in space.
We have created trouble for ourselves in the space also. How can this be stopped? Shall we stop launching new satellites and space ships? There have to be some new ways to solve the problem that we have in hand, and all countries have to unite a figure out a solution.