Despite being one of the most familiar and widely recognized natural phenomena, lightning
remains relatively poorly understood. Even the most basic questions of how lightning is …

It is now well established that both thunderclouds and lightning routinely emit x-rays and
gamma-rays. These emissions appear over wide timescales, ranging from sub-microsecond …

The response of the ocean redox state to the rise of atmospheric oxygen about 2.3 billion
years ago (Ga) is a matter of controversy. Here we provide iron isotope evidence that the …

By modifying the avalanche mode of runaway breakdown to include positive feedback from
gamma‐rays and positrons, it is found that enormous bursts of energetic radiation can be …

Terrestrial gamma-ray flashes (TGFs) from Earth's upper atmosphere have been detected
with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) satellite. The …

The Gamma‐ray Burst Monitor (GBM) on the Fermi Gamma‐ray Space Telescope detected
12 intense terrestrial gamma ray flashes (TGFs) during its first year of observation. Typical …

This review concerns the theory of the avalanche multiplication of high-energy (0.1–10 MeV)
electrons in a neutral material, a newly discovered phenomenon known as runaway …

Streamers are thin filamentary plasmas that can initiate spark discharges in relatively short
(several centimeters) gaps at near ground pressures and are also known to act as the …

In the present paper, we demonstrate that the exponential expansion of streamers
propagating in fields higher than the critical fields for stable propagation of streamers of a …

As thunderclouds charge, the large‐scale fields may approach the relativistic feedback
threshold, above which the production of relativistic runaway electron avalanches becomes …