University of Utah Cosmic Ray Physicists (image) University of Utah Caption University of Utah physicists Gordon Thomson, Charlie Jui and John Matthews discuss the Telescope Array cosmic ray observatory's discovery of a "hotspot" -- located beneath the Big Dipper in the northern sky -- emitting an unusual number of ultrahigh-energy cosmic rays. The source of these rays, which are the most energetic particles in the universe, remains unknown, but the new finding will help narrow the search. Credit Lee J. Siegel, University of Utah. Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.