Microburst precipitation phenomena.

Auroral zone microburst electron precipitation is reviewed. It can be shown from existing data that microbursts represent a major precipitation form on the dayside magnetosphere. Balloon X-ray data indicate that microbursts are periodic and they are small-scaled. Rocket and sattellite data indicate that microbursts may consist of substructures and that microburst precipitation is fractionally more enhanced along the magnetic field direction. The source of electrons appears to be nearby, _??_4Re from the surface of the earth. Microbursts are correlated to VLF and magnetic micropulsations. Study of microburst phenomena should lead to better understanding of wave-particle interaction mechanisms responsible for electron precipitation.