Researchers in a laboratory located 1km underground will begin a series of experiments to confirm the existence of dark matter, which is thought to account for much of the mass of the Universe but has never been observed. At the heart of the project - a collaboration between the University of Edinburgh, Imperial College London, the STFC Appleton Laboratory and international partners - is a super-sensitive detector that researchers hope will identify particles that constitute dark matter. Wimps, or weakly interacting massive particles, are hard to find because they do not interact with other matter easily. The detector, called Zeplin III, is based at Boulby Underground Laboratory in North Yorkshire. The facility is housed in the UK's largest commercial mine.