The collision of two lightning-bolts-in-the-making spawned an exceedingly brief but extremely energetic flash of gamma rays. This first-of-its-kind observation may help explain an origin of some of the most energetic radiation on Earth.
Researchers have for years linked the production of gamma rays to the acceleration of electrons by strong electric fields in thunderstorms. Yet they’ve never been able to pinpoint the source of any so-called terrestrial gamma ray flashes, says Yuuki Wada, an atmospheric physicist at the University of Osaka in Japan. He and his team set out to remedy that by observing a hotbed of wintertime lightning over the west coast of Japan in January 2023.