Date: 07 Dec 2001
Depicts: Illustration of black aurorae mechanism
Copyright: ESA 2001. Illustration by Medialab

The data showed that black aurorae represent holes in the ionosphere. Here, negatively charged electrons are being accelerated upwards into space inside regions known as positively charged electric potential structures.

This is the opposite process to that which creates visible aurorae, where electrons spiral down from space into the atmosphere within similar, negatively charged, structures.