Shooting old satellites and other orbiting debris with lasers is a topic of ongoing discussion — one even Australia's found itself involved in. But shooting doesn't necessarily mean destroying, according to one local aerospace company on the forefront of the problem.
EOS Space Systems, an Australian-based outfit developing "advanced electro-optic technologies" including telescopes, gimbals, coatings and of course, lasers for the space industry, believes the best way to tackle space junk is to just move it out of the way. An article on the ABC details why this is one of the more viable options, at least for now.
As Craig Smith, CEO of EOS Space Systems explains, blowing up or disintegrating the debris would not be practical, even if the technology was available. Even if we could power a laser to slice the stuff up, all we'd end up with is a bunch of smaller bits. Smith instead proposes moving the refuse out of the way, something that, surprisingly, can be accomplished with lasers.
The company's previous efforts have been focused on using beams to track orbiting objects, so it's well-placed to deal with the situation. In fact, NASA has already thrown its support behind EOS.
As for pushing around chunks of metal beyond the atmosphere, it's all a matter of applying just the right amount of energy, as Smith explains:
"By ramping up the power, photons in the light beam have momentum and energy and can transfer that momentum to the target ... And if we put enough of those photons on the target, we can very slightly change the velocity."
"If you allow that velocity to change over a period of perhaps 24 hours, then you can get actually a 100-metre shift in the location of an object to deflect it from colliding with another space debris object."
The power required to accomplish this feat is "way less than you would put into the lights in a football stadium", Smith says.
So, yeah, it's not quite on the level of Star Wars (or Star Trek, depending on your sci-fi poison), but it scores highly in the ingenuity stakes, that's for sure.