Antimatter in the air on a stormy day?

Artist's conception of antimatter in storm (NASA)

NASA Science News for Jan. 11, 2011suggests that "thunderstorms may be making antimatter:

Scientists using NASA's Fermi Gamma-ray Space Telescope have detected beams of antimatter produced above thunderstorms on Earth, a phenomenon never seen before.

Scientists think the antimatter particles were formed inside thunderstorms in a terrestrial gamma-ray flash (TGF) associated with lightning. It is estimated that about 500 TGFs occur daily worldwide, but most go undetected.

"These signals are the first direct evidence that thunderstorms make antimatter particle beams," said Michael Briggs, a member of Fermi's Gamma-ray Burst Monitor (GBM) team at the University of Alabama in Huntsville (UAH). He presented the findings Monday, during a news briefing at the American Astronomical Society meeting in Seattle.

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The GBM has detected gamma rays with energies of 511,000 electron volts, a signal indicating an electron has met its antimatter counterpart, a positron.

In which case, it is annihilated. Experimental physicists recently created 38 antihydrogen particles and preserved them for 1/10 second; here's how they kept them from mutual annihilation in a matter-based environment.

Of course, capturing one in the wild ...