How 'straight' lightning could prove the existence of dark matter: report

A group of scientists has linked the presence of macroscopic dark matter to the appearance of extremely rare "straight" lightning bolts.

"Macroscopic dark matter (macros) is a broad class of alternative candidates to particle dark matter. These candidates would transfer energy to matter primarily through elastic scattering. A sufficiently large macro passing through the atmosphere would produce a straight channel of ionized plasma," the group said in March. "If the cross section of the macro is σx⪆6×10−9  cm2, then under atmospheric conditions conducive to lightning (e.g., a thunderstorm) the plasma channel would be sufficient to seed a lightning strike with a single leader." Comparatively, they noted that ordinary bolt lightning is comprised of a "sequence of hundreds or thousands of few-meter-long leaders" strung together.