Trailblazer

摘要

One week in 1997, a mouse of a galaxy between the shoulders of Hercules turned into a monster. "It was rather inconspicuous before," says Heinz Voelk, who watched the action from the island of La Palma. "But all of a sudden it became the strongest source we've ever seen." This outburst from the galaxy Markarian 501 has left scientists in a quandary. The most energetic photons in the blast had trillions of times the energy of a visible photon, and according to the laws of physics as we understand them, they should never have made the vast journey from that galaxy to Earth. They should have been snuffed out by the sea of infrared radiation that fills space.