(Continuing coverage): A spooky-sounding technology is finding old, unmarked graves. Using hyperspectral imaging, scientists from McGill University have found unmarked animal graves with special cameras that measure changes in the light coming from soil and plants. Hyperspectral imaging collects and processes light from across the electromagnetic spectrum, including visible light, as well as ultraviolet and infrared light. The research could help police solve missing persons cases or reveal new mass graves from hundreds, if not thousands, of years ago. "As soon as there is some decay you can see a difference," said Andre Costopoulos, a professor at McGill University developing new techniques to find old graves.