A photo of a huge plasma arc next to the Andromeda Galaxy has won this year's prestigious photography prize.

A team of amateur astronomers led by Marcel Drechsler, Xavier Strottner and Yann Sainty captured the surprising discovery.

Scientists are now investigating the newly discovered giant cloud of gas.

It could be the largest such structure in the nearby environment in the Universe.

Judge and astrophotographer László Francsics said the image was as spectacular as it was valuable.

"It not only presents Andromeda in a new way, but also raises the quality of astrophotography to a higher level," he said.

The Royal Observatory Greenwich in London, which runs the Astronomy Photographer of the Year competition, also awarded two 14-year-old boys from China the Young Astronomy Photographer of the Year prize.

Runwei Xu and Binyu Wang collaborated to capture this image of The Running Chicken Nebula, IC 2944, which is located in the constellation of Centaurus, 6,000 light years away from the Earth.

Embedded in the nebula's glowing gas, the star cluster Collinder 249 is visible.

Yuri Beletsky, judge and professional astronomer, described it as a strikingly beautiful picture.

"The photographers have managed to capture the vibrant colours of the nebula as well as the embedded star cluster."

The Young Astronomy Photographer of the Year award is for people aged under 16.

The judges looked at more than 4,000 entries from around the world.

The images are on show in an exhibition at the National Maritime Museum in London from Saturday.

This image by Andreas Ettl shows the Northern Lights reflected on Skagsanden beach, Lofoten Islands, Norway.

The mountain in the background is Hustinden, which the aurora appears to encircle.