Mark Megahan
It really is a tractor beam, almost but not quite the same as described in science fiction for an eternity. The team working to develop it expects to put their design to work pulling space junk out of the way. The only thing standing in their way is cash to build and launch the prototype.
Tractor beam technology
The practical tractor beam application is still light years away from being able to hijack a spaceship under full throttle propulsion. What it can do is herd passively cooperating space junk into a safer position. The past year has seen one piece of fictional technology after another climb off the pages into our daily lives.
From beamed power transmission, to micro-miniature robots exploring inside the human body, to clothes which can regulate your temperature to keep you comfortable from the frigid ski slope to blistering desert heat.
The real life technology is called an “electrostatic tractor.” It solves the challenge of gripping a moving and rotating object without using things like harpoons, nets or brute force methods of contact.
Magnets are out of the question because they mess with all the other equipment aboard the tug craft. This solution uses “electrostatic attraction to nudge hazardous space junk safely out of Earth orbit.”
While it’s fairly easy to push space junk into a lower orbit that decays into the atmosphere, that creates even more problems. Metals vaporizing into the atmosphere is not a good thing.
Besides that, all the metal might not vaporize and huge deadly chunks could come falling out of the sky just about anywhere. That’s not a good thing either. The tractor beam drags them up into a harmless orbit or even out of Earth’s gravity well entirely.
A lot of junk
Over the past 70 years, humanity has tossed a lot of trash into space. It wasn’t garbage when it went up but it worked past it’s prime and now its useless hazardous waste. Not only that, it’s taking up huge chunks of prime orbital real estate. That’s where tractor beam technology can really help.
“With the commercial space industry booming, the number of satellites in Earth’s orbit is forecast to rise sharply. This bonanza of new satellites will eventually wear out and turn the space around Earth into a giant junkyard of debris that could smash into working spacecraft, plummet to Earth, pollute our atmosphere with metals and obscure our view of the cosmos.”
Something has to be done. This might not be the best solution but it’s a start. “While the tractor beam wouldn’t completely solve the space junk problem, the concept has several advantages over other proposed space debris removal methods, which could make it a valuable tool for tackling the issue.”
While “the science is pretty much there,” the money isn’t. “A prototype could cost millions, and an operational, full-scale version even more.” Once they have the funding, the project could be “operational within a decade.”
“The electrostatic tractor would use a servicer spacecraft equipped with an electron gun that would fire negatively charged electrons at a dead target satellite.” No matter what it’s made out of, how big it is, or how it’s rotating, “The electrostatic attraction between the two would keep them locked together.” Even 100 feet away.
“Once the servicer and target are ‘stuck together,‘ the servicer would be able to pull the target out of orbit without touching it. Ideally, the defunct satellite would be pulled into a ‘graveyard orbit’ more distant from Earth, where it could safely drift forever.“
