Cosmic Particle Accelerators Identified

摘要

For decades, physicists thought they knew where many of the immensely energetic protons and atomic nuclei that whiz in from space as cosmic rays get their start: in the wreckage of exploded stars, or supernovas. Now they're sure. This year, researchers with NASA's orbiting Fermi Gamma-ray Space Telescope produced the first direct evidence of such particles revving up in cloudlike supernova remnants within our galaxy.