News Planetary Science

A rain of electrons causes Mercury’s X-ray auroras

The discovery hints that auroras on all planets except Neptune have a common explanation

An illustration of the BepiColombo probe with Mercury in the background.

With new data from the BepiColombo probe (illustrated), scientists have shown that electrons rain down on the surface of Mercury, causing its X-ray auroras.

ESA, ATG medialab

By Elise Cutts

Mercury’s auroras are perfectly in character. While temperate Earth gets heavenly light shows over its poles, hellish Mercury gets invisible ribbons of X-ray radiation that cling to its sun-blasted surface.