June 3, 2009 Florida Institute of Technology researchers are
trying to solve one of the great mysteries in nature: how
thunderstorms make lightning. Because, in principle, lightning
is a big spark it should behave like other sparks—like the ones
created when we touch a door knob on a dry day. Scientists have
accumulated evidence, however, that lightning sometimes behaves
in very un-spark-like ways. Lightning can start in regions of
thunderstorms that have relatively low electric fields and, so,
should create no sparks. Because lightning obviously is made by
thunderstorms, scientists are left wondering what they are
missing. Three such scientists, Joseph Dwyer and Hamid Rassoul
from Florida Tech and Martin Uman from the University of Florida
developed a new technique to remotely measure thunderstorm
electric fields on the ground. By measuring small radio pulses
made by cosmic-rays passing through these storms, they calculate
that they can reconstruct the electric fields along the high-
energy particle's paths.