Ever since we started exploring space over fifty years ago, we have sent out probes, launched satellites, built a space station and propelled innumerable amounts of scientific above Earth. At some point, machines break down, outlive their useful lives, or become obsolete and are eventually replaced by a newer model or upgraded version. However, the out-of-date technology doesn’t come back to Earth, it stays in orbit as space debris, which, over the years, has only broken apart further, and accrued a significant amount.
If it sounds precarious, it’s because it is. The European Space Agency (ESA) estimates there are over hundreds of millions of space debris currently orbiting Earth. Although most are small fragments a millimetre wide, the ESA believes there are 750,000 “flying bullets” or objects around a centimetre in size, 20,000 objects over the size of ten centimetres, and 5,000 above the size of a meter. Whilst most space agencies are able to track and detect large pieces of space debris, they are concerned, as the ESA’s head of operations Rolf Densing recently told the press.
Collisions, although rare, are the primary reason for the ESA’s repositioning of its’ satellites, with the European agency usually receiving several collision warnings a year. But with an exponential rise in space debris, agencies are becoming more and more nervous about a large scale collision. The odds of such a large scale collision increases at the same rate as the accumulating amount of space debris, with scientists believing that only one such event could create a dense, impenetrable cloud of debris.
There has yet to be such an event, but with over 600 active satellites present, it could only be a matter of time. Those satellites provide us with everything from science and Earth data, telecommunications and entertainment and the amount of information that could be lost should some of those satellites be destroyed or damage is fairly significant.
The growing amount of space debris has been weighing on scientists’ minds. Although a certain amount re-enters our atmosphere and burns up before reaching us, there is still a large portion that continues to pose a problem. The ESA, as well as the Japanese Aerospace Exploration Agency (JAXA) have been researching methods to clean up space debris, everything from giant nets no magnet-powered recovery systems. Earlier this year, JAXA recently launched their first clean-up satellite, but it unfortunately failed, sending them back to the drawing board.