"Tractor beams" could soon move from science fiction to science fact, thanks to a NASA-funded study. Ideas for tractor beams—"the ability to trap and move objects using laser light," explains NASA—have been published, but none has been put into practice. "Though a mainstay in science fiction, and Star Trek in particular, laser-based trapping isn't fanciful or beyond current technological know-how," says the scientist whose group got $100,000 in research funding for the study.
In theory, the beams could gather samples so a planetary rover could examine them. One method involves trapping objects under a principle known as "optical tweezers," though it needs an atmosphere to operate, explains the BBC. The other two use specially shaped laser beams, in which the intensity peaks in locations other than the center; one such beam has already been found to have pulling power.