The phrase “Tractors in Space” may conjure visions of floating farm equipment; But it turns out that tractor beams – long a staple of Star Trek and other speculative fiction – may actually work. Furthermore, tractor beams may soon be pulling in particles of planetary dust for robotic probes to study. NASA laser scientists are looking at three concepts. Each one uses lasers to draw in very small, low mass objects. Picture a robot directing a vacuum cleaner’s suction hose. One method – known as “optical tweezers” sends out a pair of spinning beams. Matter is pulled into the dark corridor between the beams. Another – called an “optical solenoid” – uses the laser’s spiraling intensity peaks to pull particles back along the length of the beam and will work well in the vacuum of space A third approach – named the Bessel beam – has never before been tried but may leverage concentric rings of light to snag motes of matter. But what if you needed to change the course of something very large; like an asteroid? Others at NASA – and outside the agency – are considering how a small spacecraft, flying formation with an asteroid over a long period of time might exert just enough gravitational force on the asteroid to alter its orbit. A worthy job indeed for a tractor in space. And for SPACE.com, I’m DB
Long known in science fiction, tractor beams may be used by NASA probes to pull in tiny particles for scientific study. “optical tweezers,” “optical solenoids,” and “Bessel beams” are each under study by NASA’s Innovative Advanced Concepts program.
Credit: SPACE.com / NASA / DigitalSpace