Astronomers find aurora a million times brighter than the northern lights

The most powerful aurora ever recorded has been spotted above a failed star 18 light years away, solving a longstanding astronomical mystery

The sky above a failed star in a distant constellation shimmers with a beautiful green and yellow aurora one million times brighter than the northern lights. The spectacular light show is the first confirmed aurora on a body outside the solar system, and the most powerful ever recorded.

Astronomers detected the celestial display when they trained some of the world's most sensitive telescopes on a brown dwarf that lies 18 light years away in the constellation of Lyra. The aurora's colourful streaks wave green and yellow when oxygen and sodium are battered by electrons in the brown dwarf's atmosphere. The brightest light the telescopes picked up was from hydrogen, which glow redder than the eye can see.