(IMAGE) Helmholtz Association Caption This is the spectrum of cosmic rays with the knee and the ankle. While the knee is measured at different energies for light and heavy primary particles, KASCADE-Grande has now for the first time revealed an ankle-like structure for light primary particles. Credit KIT Usage Restrictions None 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.