Physicists have spotted the highest-energy light ever seen. It emanated from the roiling remains left behind when a star exploded.
This light made its way to Earth from the Crab Nebula, a remnant of a stellar explosion, or supernova, about 6,500 light-years away in the Milky Way. The Tibet AS-gamma experiment caught multiple particles of light — or photons — from the nebula with energies higher than 100 trillion electron volts, researchers report in a study accepted in Physical Review Letters. Visible light, for comparison, has just a few electron volts of energy.“This energy regime has not been accessible before,” says astrophysicist Petra Huentemeyer of Michigan Technological University in Houghton, who was not involved with the research. For physicists who study this high-energy light, known as gamma rays, “it’s an exciting time,” she says.