Why dig into the surface of Mars when you can beam bits of soil into a container instead? Or perhaps you can pluck some samples out of the thin Martian air and forego a landing entirely?
Science fiction? Of course. Science fact? Not if a team of cutting-edge NASA researchers can figure out how to use tractor beams to trap and move objects using laser light.
The team, which is based at NASA's Goddard Space Flight Center in Greenbelt, Md., won a $100,000 study grant to look into three different techniques for using laser light beams to collect and move particles, much the same way, albeit on a much smaller scale, than the fictional Starship Enterprise, of television’s "Star Trek" series, used tractor beams to shift wayward asteroids or latch on to visiting vessels.
The advantage of using tractor beams for snaring samples, over traditional methods, like gel capture, is that the beams can collect materials over time and at greater distances.
Aerogel, for example, a lightweight substance used to snare comet particles, is a "one and done," laser engineer Paul Stysley, lead project researcher at NASA's Goddard Space Flight Center in Maryland, told Discovery News.
"You grab whatever particles you can when you fly through the comet and you bring them home. If you have a spacecraft following a comet and continuously grabbing particles can study the state of the comet, or whatever, over time," he said.
He and two colleagues want to figure out which of three techniques is best suited for collecting samples and perhaps build the skeleton of a machine to do the job.
One technique, the team says now least-promising, uses Bessel beams, which is a beam that has rings of light around its central point. Scientists believe the beams, which look like ripples in water, could trigger electric and magnetic fields in the path of an object. In theory, particles would move backward as they bump into the fields, as described by a team of Chinese and Hong Kong scientists in a paper published on the electronic archive arXiv.org in February. The concept has not yet been demonstrated in a lab.
Another technique uses a pair of beams to work like optical tweezers. If the beams come from opposite directions, they create a ring-like field that traps particles where they overlap. Strengthening or weakening one beam’s intensity causes air around the trapped particle to heat or cool, causing it to move.
The idea, proposed in 1986 and prototyped by the University of Chicago in 1997, has been tested as a way to move tiny objects on microchip and to create new types of photonic devices, such as optical microscopes and computers that run on light. Currently, this technique, the most mature the batch, wouldn't work without an atmosphere, even a puny one like the one on Mars.
The third idea, called optical solenoid beams, would work in a vacuum. It entails tilting electromagnetic waves to induce motion in particles.
The project is among 30 pioneering technologies selected by NASA for study grants and a new program to explore far-out ideas.
"It's essentially the first analysis to see if a revolutionary concept is feasible," Jay Falker, who oversees the NASA Innovative Advanced Concepts program at agency headquarters in Washington DC, told Discovery News.
The agency, which received more than 700 proposals, expects to decide next year which projects will receive follow-on grants for additional work. Stysley intends for his team to be among them.
"We're reasonably confident that something could be created that could be used on a future mission," Stysley said.
© 2012 Discovery Channel