NASA is going to begin a study that evaluates not one, not two, but three methods for making once sci-fi tractor beams into a reality.
But before we all get too excited pulling out our Star Trek reruns to see how the ship is able to pull massive objects toward it using a special laser, NASA comes right out and says it won't be as exciting as that:
"The original thought was that we could use tractor beams for cleaning up orbital debris," Principal Investigator Paul Stysley said on NASA's website. "But to pull something that huge would be almost impossible -- at least now. That's when it bubbled up that perhaps we could use the same approach for sample collection."
But still an exciting technological move none the less. The researchers hope to determine which technique works best in collecting small amounts of terrestrial samples. One technique is the "optical tweezers" method, which uses two beams to trap the particles. NASA's news release explains:
The resulting ring-like geometry confines particles to the dark core of the overlapping beams. By alternately strengthening or weakening the intensity of one of the light beams -- in effect heating the air around the trapped particle -- researchers have shown in laboratory testing that they can move the particle along the ring's center. This technique, however, requires the presence of an atmosphere.
Another technique uses solenoid beams that relies on electromagnetism and could be used an space without an atmosphere. And the final technique has never been previously tested like the other two: it involves a special kind of laser called a Bessel beam, which creates rings of light around a central dot as opposed an ordinary laser with just one point. Researchers believe that the electric and magnetic fields created could pull an object back toward the laser, against the beam itself.
Watch this hypothetical mission of how tractor beams could be used to collect samples in space:
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