A NASA spacecraft discovers antimatter bursts released by thunderstorms.
Thunderstorms produce more than just lightning. As these powerful storms roll over Earth, their electric fields can eject a burst of gamma rays known as a terrestrial gamma-ray flash. And now scientists have discovered that these flashes also create the asymmetrical opposite of matter—antimatter. NASA's Fermi Gamma-ray Space Telescope was designed to monitor gamma rays, the highest-energy form of light, in outer space. But it also observes these flashes from thunderstorms. In 2009, Fermi detected gamma rays from a thunderstorm that was located well beyond the horizon from where it could directly observe the storm. So where did the rays come from? When antimatter collides with matter, the particles annihilate and emit gamma rays. This means the gamma rays detected by Fermi could only have come from an antimatter collision with the spacecraft itself, providing the first-ever clue that these Earth-bound storms can send antimatter into space. In the videos below, see a map of terrestrial gamma-ray flashes detected by Fermi and a breakdown of how this explosive, mysterious process unfolds.