In the 2013 film "Gravity," a chain reaction of orbital collisions creates a cascade of debris circling the Earth at 17,000 mph. It's a spectacular dramatization of a very real threat. Because, as Julian Huguet explains in this DNews report, there's a lot of junk in orbit.
In addition to the satellites and space stations we've put in space, we've left a lot of litter up there. NASA keeps track of the bigger stuff and even publishes a newsletter called Orbital Debris Quarterly. Really. Still, the threat of a chain reaction increases every year.
Efforts into cleaning up space go back to at least 1996, when a special gel was put on the outside of the space station Mir, in an attempt to gather microscopic space junk. Since then, pretty much every space agency and aerospace company on the planet has proposed plans.
In 2012, Raytheon tested phase one of its Space Debris Elimination concept. The idea: A device suspended by balloons 80 km up would shoot a jet of atmosphere 600 km into space, snagging low-orbit junk and dragging it back to Earth.
The Japanese recently tried out a magnetic space net that pulls debris toward it, then burns it up on re-entry into the atmosphere. Last year, Swiss engineers at EPFL proposed a similar approach, designing a spacecraft that could grab up medium-sized orbital debris in a giant space cone.
The U.S. Air Force, meanwhile, has been developing a concept it calls a "laser broom" since the 1990s. Using ground-based laser cannons, scientists would vaporize select portions of space debris whizzing by overhead. The resulting vapor would create enough drag to slow the target and let it burn up in the atmosphere.
Julian has more specifics in the video, plus some good Star Wars jokes. Or feel free to dig deeper with our recent investigation into falling space balls.
-- Glenn McDonald
Wired: The Mad Plan To Clean Up Space Junk With A Laser Cannon
NASA: Orbital Debris Quarterly News
Extreme Tech: Japan Is Preparing To Launch A Giant Magnetic Net That Will Trawl Space For Junk