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An aurora has been spotted outside our Solar System for the first time, scientists report.

An international team detected the light display around a brown dwarf about 18 light years away in the Lyra constellation.

They say the luminous glow looks like the Northern Lights, but is up to a million times brighter and more red than green in colour.

Dr Stuart Littlefair from the University of Sheffield said: "This is the first time that we have confirmed we are seeing auroras on brown dwarves."

Shimmering auroras are some of the Earth's most dazzling displays. This luminous glow can also appear around all the planets in our Solar System.

They are caused when charged particles from the Sun interact with the atmosphere.

But the illuminated brown dwarf, an object which is too small to have become a star but too massive to be a planet, lies further out in the galaxy.

The dwarf is called the LSR J1835 and was observed using the Very Large Array radio telescope and the Hale and Keck optical telescopes.

The scientists watched the object as it quickly rotated, and observed how the light changed.

The dwarf's aurora is mainly red in colour because the charged particles are mainly interacting with hydrogen in its atmosphere. On Earth, the greenish glow is caused as the electrons from the Sun hit oxygen atoms.

Scientists are puzzled about how the light show is being made but the discovery is helping them to understand more about brown dwarves.

The findings are reported in the journal Nature.