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Cosmic revelation heralds new way to view the stars

点击量:   时间:2017-12-05 04:02:11

By Hazel Muir “IT WAS as if they went out to catch butterflies and caught an F-111 aircraft.” This often-quoted line captures just how surprised researchers were when an astonishingly energetic particle from space was caught in an experiment in 1991. Since then they have puzzled over the origin of such rare bullets, called ultra-high energy cosmic rays. While lower energy cosmic rays are known to come from the sun and other sources within our galaxy, such as the remnants of supernova explosions,