Interferometric radar observation of fast moving meteor trails in strong electric field

Abstract:

Usually, at mid-latitudes, field-aligned irregularities cause non-specular trails while in the polar region long-lasting irregularities are possibly sustained by charged meteor dust. Unusual, non-specular, fast-moving meteor trail echoes are observed in the summer polar mesosphere at Kiruna, Sweden. The unusual meteor trails propagate downward and upward at speeds of a few kilometers per second along a slanted path between 87-93 km altitudes, merging in the middle and lasting for several seconds. Here we propose that an electrical discharge is responsible for these trails. The corresponding horizontal electric field for the observed speeds is estimated up to tens of volts per meter at 90 km. Both the long-lasting merging of two fast-moving plasma trails likely suggest a new type of meteor-trail leader discharge occurring in the summer polar upper mesosphere.