Spacecraft detect powerful gamma-ray flares from a supernova remnant known for its steady glow
HEIDELBERG, Germany — Astronomers consider the Crab nebula one of the steadiest sources of high-energy radiation in the universe. Radiation from the supernova remnant is believed to be so constant that astronomers use it as a standard candle with which to measure the energetic radiation of other astronomical sources.
That’s why researchers are astounded that two spacecraft recently recorded giant gamma-ray hiccups from the Crab, the remnants of a stellar explosion 6,500 light-years from Earth that was observed by humans in 1054. The intensity