Galactic Glare Reveals Birthplace of Cosmic Rays

摘要

Cosmic rays-charged particles that hurtle through space at nearly the speed of light-have long baffled scientists. How do they acquire such tremendous velocities? Two new astronomical results-one in this week's issue of Science and the other published online this month in Nature-suggest that the physicist Enrico Fermi nailed the answer 60 years ago: They get their oomph from exploding stars. The papers give "pioneering results on a subject that was only explored by theorists" until recently, says Avi Loeb, an astrophysicist at Harvard University who was not involved in either study.