Tractor beam is capable of analysing space debris

A team headed by Paul Stysley at NASA’s Goddard Space Flight Center has received $100,000 (£62,777) to study three experimental methods for capturing particles and transporting them via laser light to an instrument.

‘The original thought was that we could use tractor beams for cleaning up orbital debris,’ Stysley said. ‘But to pull something that huge would be almost impossible — at least now. That’s when it [occurred] that perhaps we could use the same approach for sample collection.’

The first experiment centres around an ‘optical tweezers’ method of using two counter-propagating lasers. 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 centre. This technique, however, requires the presence of an atmosphere.

Another technique employs optical solenoid beams whose intensity peaks spiral around the axis of propagation. Testing has shown that the approach can trap and exert a force that drives particles in the opposite direction of the light-beam source. Unlike the optical vortex method, this technique relies solely on electromagnetic effects and could operate in a space vacuum.