Cosmic Ray Spectrum (IMAGE) University of Delaware Caption This scientific figure of the cosmic ray energy spectrum, provided by researcher Bakhtiyar Ruzybayev at the University of Delaware, shows the steepening at the "knee." Below the knee, cosmic rays are galactic in origin; above that energy, particles from more distant regions in our universe become more and more likely, he says. Credit Bakhtiyar Ruzybayev/University of Delaware Usage Restrictions Image must include credit to University of Delaware License Licensed content 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.