Mercury's x-ray aurora proves it's the most goth planet

Scientists have known for years that Mercury's crust fluoresces, and now they know why.

Until recently, Mercury seemed to be the only planet in our Solar System without aurorae, those streams of light that appear on Earth in the polar skies when solar wind bombards the upper atmosphere with electrons.

Mercury has no atmosphere for an aurora to appear in, after all, just a thin layer of atoms blasted free of its surface by meteoroids and solar wind. According to a recent study of data from the BepiColombo mission, Mercury has x-ray aurorae that make the ground itself glow with invisible light. As strange as the phenomenon is, though, JAXA planetary scientist Sae Aizawa and her colleagues say it’s caused by the same physics that create the familiar Northern Lights here on Earth. FULL STORY from Inverse