You’ve seen them used in Star Trek, Star Wars, and all sorts of other classic science fiction for decades. Now tractor beams are on the verge of becoming a reality, at least if NASA has its way. They’re funding a study of the technology, in the hope that developing it can reduce mission risk.
If you’re unfamiliar with how a tractor beam is supposed to work, here’s a quick thumbnail sketch. Tractor beams, in theory, are guided streams of energy which can be used to either attract or push away an object. In science fiction, for instance, the Enterprise would use a tractor beam to guide a stalled shuttlecraft safely into its hanger deck. NASA has similar uses in mind for the technology, should it become a reality.
The BBC says they’ve already narrowed it down to the three most likely ways to develop tractors. Here’s a quick breakdown of the three ways they plan to approach it…
OPTICAL TWEEZERS: Objects are trapped in the focus of one or two laser beams. The drawback to this method is that it will only work in an atmosphere.
SOLENOID BEAMS: A laser with the intensity of it focused around the beam in a spiral, instead of peaking in its center and then tailing off, like a normal laser. These have already worked in lab tests.
BESSEL BEAMS: A laser with intensity that rises and falls in peaks and troughs along the beam’s line. These haven’t been proven in lab experiments yet.
So how close is this to actually happening? NASA is investing only $100,000 which, in terms of research money, doesn’t sound like a lot. At least it’s a start, though it’s worth noting that all three methods, even if they work, will only have a very small effect. The effect they have is never going to be enough to duplicate what you may have seen being done with tractor beams in Star Trek. The hope here seems to be that once a proven method is found, they’ll be able to increase the power of the beams exponentially.