Not satisfied to clutter up Earth, we’re spreading our trash to our planet’s orbit, too — we’ve produced an estimated 8,262 tons of space junk. But a team of scientists has a new plan to get rid of the largest of those discarded satellites, tools, and bits of spacecraft: zap them with a plasma beam. Researchers at Japan’s Tohoku University outlined their idea in a study published last week in the journal Scientific Reports.
Their idea: fit a satellite with a type of propulsion system known as a helicon plasma thruster, then shoot space junk with the beam of plasma it produces. The force of the carefully aimed shot will knock a piece of space junk out of Earth’s orbit and into the atmosphere where it will burn up.
Of course, shooting this beam out of the satellite will push the satellite itself in the opposite direction (see: Newton’s third law of motion). This would make it difficult to remain close enough to the space junk to effectively push it. To avoid this problem, the researchers suggest adding another plasma beam to the satellite, this one facing in the opposite direction of the first. That’ll push the satellite back into position.
When the team tested a version of this system in a laboratory space simulation chamber, a room that replicates the environmental conditions of space, they found that they were able to control it exactly as they had hoped.
The researchers didn’t give a precise estimate for how long such a satellite could patrol the skies, but in a press release, one of them predicted it would be able to “undertake long operations.” And given that fact that our littering in space is on track to get worse in the future, a long-term solution is just what we need.
READ MORE: Plasma Thruster: New Space Debris Removal Technology [Tohoku University]