US space agency Nasa has funded a study of "tractor beams" to gather samples for analysis in future missions. The $100,000 (£63,000) award will be used to examine three laser-based approaches to do what has until now been the stuff of science fiction. Several tractor-beam ideas have been published in the scientific literature but none has yet been put to use. Nasa scientist Paul Stysley says the approach could "enhance science goals and reduce mission risk". "Though a mainstay in science fiction, and Star Trek in particular, laser-based trapping isn't fanciful or beyond current technological know-how," said Dr Stysley of...