The fact that humans dump their trash wherever has already cost us the depletion of our environment and its natural resources. Sadly, this is a problem that isn’t just limited to our planet now. According to NASA, there are about 500,000 pieces and chunks of space junk orbiting the earth. The space junk, formally called orbital debris, is made out of old satellite pieces, used rocket parts, and other pieces of rock chipped off from asteroids and such.
These debris poses a grave danger to currently functioning satellites and shuttles, and even the International Space Station itself. In addition, because of the earth’s gravity, the orbital debris can travel at speeds of up to 28163 km/h. This means than an impact from even a tiny piece of debris can cause massive damage to any spacecraft or equipment. “The greatest risk to space missions comes from non-trackable debris,” says Nicholas Johnson, NASA chief scientist for orbital debris.
Because of this, several companies have proposed ways of cleaning up these annoying pieces of space junk.
e.DeOrbit. Source: Space
One method is the e.DeOrbit. The project was proposed by Clean Space, a part of the European Space Agency (ESA) back in 2014. The idea is to either use nets or robotic arms to catch the debris, drag it out of orbit, and throw it into a lower altitude of the earth’s atmosphere, where it’ll burn up into nothing. It’s projected to launch in 2023.
Another possibility is the CleanSpace One, which was initially developed to de-orbit Switzerland’s SwissCube nanosat. The plan is to launch the device from the SOAR spaceplane, an unmanned mini-shuttle, and then use it to fling the junk with enough force to bring it out of orbit and into the atmosphere where it’ll then burn up. It’s projected to launch in as soon as 2018.
Finally, there’s the Electrodynamic tether project proposal by Japan’s space agency, the JAXA. With an electrified tether cable of over 700 meters long attached to a 20 kilogram counterweight, it aims to zap orbital debris to slow it down and bring it out of orbit and into the atmosphere, where it can burn up safely.
Of course, there are several other proposed methods other than these, though they haven’t really progressed in development these past few years. One alternative method is to catch debris and sling it into the atmosphere, or using a solar sail to capture and burn the debris then and there. Others have suggested using a net that’s 3 kilometers wide to knock the orbital debris out of orbit, and finally, sending balloons in space to blow the debris into the atmosphere.