DURHAM, N.H., May 13 (UPI) -- What exactly coaxes the first lightning bolt from storm clouds? What initiates the charged strike and bellowing thunder? A new study suggests pockets of anti-electron clouds could have something to do with it.
Researchers at the University of New Hampshire recently gathered some surprising, yet puzzling, insights into the world of lightning formation when a research plane they were on found its way into the top of an active thunderstorm.
While riding aboard a Gulfstream V, operated by the National Center for Atmospheric Research, a team of scientists found themselves unexpectedly in the midst of a violent storm. While passing through the storm clouds, the researchers' instruments picked up a strange phenomenon -- a cluster of positron clouds.
Positrons are the antimatter opposite of electrons, and typically come complete with physical byproducts like intense gamma-ray emissions. But no gamma-ray energy was observed, and the presence of the anti-electron clouds seemed to defy the scientists' current understanding of physics.
While most of the observable world is made up of normal matter, the laws and theories of physics suggest that for all normal matter there is corresponding antimatter. When normal matter and antimatter meet -- such as when an electron and positron come together -- they both are annihilated and their destruction results in a intense burst of gamma rays.
"The fact that, apparently out of nowhere, the number of positrons around us suddenly increased by more than a factor of 10 and formed a cloud around the aircraft is very hard to understand. We really have no good explanation for it," University of New Hampshire physicist Joseph Dwyer said in a press release. Dwyer is a lightning expert at the New Hampshire's Institute for the Study of Earth, Oceans, and Space.
Thunderstorms are known to sometimes produce brief flashes of gamma rays, producing both electrons and positrons as the rays strike the air. But researchers did not record any gamma rays in the immediate vicinity of the positron clouds.
It's possible the positron clouds are a sign of a theoretical phenomenon called dark lightning, whereby high-energy particles are accelerated, producing positrons and helping discharge storm clouds.
"In detecting the positrons, it's possible we were seeing sort of the fingerprint of dark lightning. It's possible, but none of the explanations are totally satisfying," Dwyer said.
Dwyer and his colleagues are admittedly fascinated by their harrowing, yet eye-opening experience. But they aren't necessarily any wiser for it.
"We really don't understand how lightning gets started very well because we don't understand the electrical environment of thunderstorms," Dwyer acknowledged. "This positron phenomenon could be telling us something new about how thunderstorms charge up and make lightning, but our finding definitely complicates things because it doesn't fit into the picture that was developing."