Revellers celebrate moments before the rocket fire or “Txupinazo” marks the start of the Festival of San Fermin (or Sanfermines) at Consistorio square in Pamplona, Spain, 06 July 2014. The annual nine day long running-with-the-bulls fiesta commemorates St. Fermin, Pamplona's patron saint. (Photo by Javier Lizin/EFE)

A visitor walks inside the initiation well at Quinta da Regaleira in Sintra October 6, 2014. Sintra became the first centre of European Romantic architecture in the 19th century, which influenced the development of landscape architecture throughout Europe. It was classified as a World Heritage Site by UNESCO in 1995. Its monuments are visited by more than 1.5 million of tourists every year, according to local media. (Photo by Rafael Marchante/Reuters)

A couple chats at a park during sunset in Chihuahua November 15, 2014. (Photo by Jose Luis Gonzalez/Reuters)

Chincoteague Ponies swim across Assateague Channel in a heavy downpour on Wednesday, July 24, 2013 during the 88th Annual Chincoteague Pony Swim. A portion of the herd will be auctioned on Thursday. (Photo by Jay Diem/Eastern Shore News)

Starting on Monday, August 12, Perseid meteors will streak across the summer sky for a couple of nights, offering casual stargazers and serious nighttime photographers a chance to capture a glimpse of the annual meteor shower. Photo: Photographer David Kingham created this composite image from 23 photos on August 12, 2012. (Photo by David Kingham)

The Royal Observatory just announced its Astronomy Photographer Of The Year 2013 winners. Australian photographer Mark Gee was chosen among a thousand amateur and professional photographers around the globe to win the top title. His work is part of an exhibition of the winning photographers, which opened on Sept. 19 at the Royal Observatory Greenwich. The Royal Observatory shared with us the winners and notable mentions of the competition. Their descriptions of the prizewinners can be found below the images.

Ingots of 99.99 percent pure silver are cast at the Krastsvetmet Krasnoyarsk non-ferrous metals plant in the Siberian city of Krasnoyarsk, Russia, June 5, 2015. Krastsvetmet is one of the world's largest players in the precious metals industry. REUTERS/Ilya Naymushin

A soldier walks on the bank of the river in central Pyongyang, North Korea on April 16, 2017. (Photo by Damir Sagolj/Reuters)