The Spectrum of Cosmic Rays with Knee and Ankle (image) Helmholtz Association Share Print E-Mail 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 Share Print E-Mail 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.