By Andrew Grant
High-speed particles from space are helping to unravel a high-voltage mystery in the clouds.
Astronomers have determined the strength of electric fields in thunderclouds by detecting the radio wave signature of cosmic ray particles striking the atmosphere. Reported April 24 in Physical Review Letters, the research offers insight into the confluence of cloud conditions that leads to lightning strikes, which atmospheric simulations cannot explain. The technique could also validate an intriguing hypothesis that cosmic rays provide the spark that triggers lightning.