GAMMA rays that originate on Earth during lightning storms occur more frequently than previously thought, and are more energetic than those generated by cosmic events such as the birth of black holes.
Terrestrial gamma-ray flashes were discovered in 1994 by NASA’s orbiting Compton Gamma-Ray Observatory. But they have been accurately measured for the first time by NASA’s RHESSI satellite, which was launched in 2002. Astronomers say that at least 50 such bursts of high-energy photons occur on Earth every day. The average energy per photon in these flashes is higher than that seen in gamma rays coming from space, says David Smith, a physicist at the…
