One Step Closer to Tricorders, with Handheld Device that Identifies Life Forms

Using nothing more than a battery-powered device that emits a beam of ultraviolet light, future robotic explorers will be able to identify the building blocks of life on other planets and moons. A group of scientists in the U.S. and the U.K. have developed a small device which uses a low-power laser beam to sweep over rocks or soil, identifying identify organic substances that are the signposts of life as we know it. Specifically, the little machine "sees" life by causing polycyclic aromatic hydrocarbons (PAHs), often called the earliest form of organic matter in the universe, to light up. The discovery is so promising that it's likely to be launched out with the next generation of Mars rovers. - io9