Breakthrough Discovery: NASA Plane Detects New Type of Gamma-ray Emission in Thunderclouds

A NASA plane has become a linchpin in understanding the mysterious inner workings of thunderclouds, leading to the discovery of a novel type of gamma-ray emission dubbed the flickering gamma-ray flash. This groundbreaking finding helps bridge the gap in comprehending thundercloud radiation, ultimately contributing to more precise risk assessments of lightning for individuals, aircraft, and even spacecraft.

The international team behind this revelation includes researchers from the University of Bergen, Norway, who spearheaded the study in cooperation with numerous prestigious institutions, such as NASA's Marshall and Goddard Space Flight Centers, the U.S. Naval Research Laboratory, and several universities across the Americas and Europe. Detailed in a pair of articles in the scientific journal Nature on October 2, the discovery had its roots in an intricate airborne mission on NASA's ER-2 research aircraft during July 2023.

Departing from MacDill Air Force Base in Tampa, Florida, the ER-2 undertook 10 distinct flights above tropical thunderclouds situated over the Caribbean and Central America. While performing figure-eight patterns several miles up in the sky, the aircraft collected extraordinary data on cloud activities using a suite of detectors designed for the Airborne Lightning Observatory for Fly’s Eye Geostationary Lightning Mapper Simulator and Terrestrial Gamma-ray Flashes campaign.

While the researchers were initially focused on detecting terrestrial gamma-ray flashes (TGFs) associated with lightning strikes, the new flickering gamma-ray flashes they encountered were an unforeseen discovery. These flashes, each persisting for about 50 to 200 milliseconds, were found to be too transient for detection via space-based instruments, but the proximity afforded by the high-altitude flights enabled scientists to identify more than 25 instances.

This research, seizing an innovative and cost-effective approach through the use of aircraft over satellites, has amassed significant findings: not only the detection of over 130 TGFs – a volume that far exceeded initial expectations – but also the identification of these intermediate-duration gamma-ray flashes.

The significance of these discoveries stretches far beyond scholarly intrigue; they provide vital insights into thunderstorm dynamics that have the potential to save lives. Lightning, a common byproduct of thunderstorms, is renowned for its destructiveness, and advancements in understanding these natural phenomena can lead to better protective measures for the populace.

As more aspects of lightning and thundercloud radiation unfold, meteorology stands at the cusp of a new era of discovery. By shedding light on these gamma-ray emissions, scientists are piecing together the dynamic puzzles that thunderclouds pose, unraveling secrets that have hovered, quite literally, above us for ages.