We've been waiting for honest-to-goodness tractor beams since Shatner was still sitting in the captain's chair. Now—finally—NASA's investing real cash money to spur the development of Zero Point technology.
NASA is funding studies on three specific laser-based technologies. The most well known is the "optical tweezer" method which employs a hollow laser beam to move small objects using air pressure differences. Problem is—it needs an atmosphere in order to work. The Solenoid beam's proven propulsion method pushes objects using intensity peaks that corkscrew around a central beam. Bessel beams, on the other hand, trap and transport objects in a series intensity troughs that resemble a sine wave—though they haven't successfully pulled an object, only pushed.
Sure, none of these methods can pick up much—or carry it very far—at the moment. However, with some improvements to efficiency and output, these devices could one day replace mechanical scoopers, grappling arms, and all those other important bits on interplanetary landers that seem to break the second they leave Earth's atmosphere.
Readying tractor beams for future interplanetary exploration is a great goal, I suppose. But really I just want to know where I can pick up a Half-Life 2-style Gravity Gun. [BBC News - Image by Thomas Harriman]