Lightfoils

A little light goes a long way. Researchers at the Rochester Institute of Technology in New York have created lightfoils—a way to generate lift and steer small objects through space.

Publishing in yesterday’s issue of Nature Photonics, the researchers demonstrated how moving laser light through a small glass object could lift the object into the air.

According to Science News:

Researchers have known for a long time that blasting an object with light can push the object away. That’s the idea behind solar sails, which harness radiation for propulsion in space, for instance.

Dubbed “lightfoils”, these wing objects are similar to airfoils, which make airplane wings well shaped and engineered and allow them to lift  off the ground. Pressure from light creates lift for objects that refract light, like glass. From Science Now:

Because glass bends light, a property known as refraction, the wing moved perpendicular to the light rays at a rate of a few micrometers per second, as seen in this video.

Stunningly, the lift from light is quite dramatic. Again from Science News:

These lightfoils’ lift angles were about 60 degrees, the team found. “Most aerodynamic things take off at very gradual angles, but this has a very striking, very powerful lift angle,” [lead author Grover] Swartzlander says. “You can imagine what would happen if your airplane took off at 60 degrees — your stomach would be in your feet.”

But don’t expect any aircraft made with optical wings anytime soon—lightfoil only works on a micro-scale. One application may be to better steer solar sails like those on Japan's IKAROS spacecraft, launched this past summer. In addition, according to Nature News:

The lightfoil concept could also be used to power micromachines, or transport particles in liquids.

Image: Swartzlander et. al.