An aerial view shows a Russian Troika, a sledge drawn by three horses, competing on the ice-covered Yenisei River during the annual Ice Derby amateur horse race near the Siberian settlement of Novosyolovo, south of Krasnoyarsk, Russia March 17, 2018. (Photo by Ilya Naymushin/Reuters)

Three white tigers cub born on January 05, 2020 stand beside their mother Orissa at the zoological park of Amneville, northeastern France, on March 9, 2020. (Photo by Jean-Christophe Verhaegen/AFP Photo)

Sloth “Paula” hangs from a branch in her enclosure at the zoo in Halle an der Saale, eastern Germany, on June 14, 2019. The two-toed sloth celebrated her 50th birthday and is, according to the zoo, the oldest sloth of the world. (Photo by Hendrik Schmidt/dpa/AFP Photo)

Charli XCX performs on day three of the Pitchfork Music Festival at Union Park on July 21, 2019 in Chicago, Illinois. (Photo by Michael Hickey/Getty Images)

Folk dancers from Chile participate in a folk dance festival in Bitola, North Macedonia on July 26, 2023. (Photo by Ognen Teofilovski/Reuters)

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.

Jesse Larios, 33, from Los Angeles, wears a bear suit while walking along Hollister Road in Gilroy, California, U.S., April 21, 2021. Larios, also known as Bear Sun on social media, is walking from his home in Los Angeles to San Francisco while wearing the bear suit as a social media fundraising event. (Photo by Brittany Hosea-Small/Reuters)

The secretive indri (Indri indri) of Madagascar, the largest living lemur. It is also critically endangered and highly evolutionarily distinct with no close relatives, which makes its branch one of most precarious on the mammal evolutionary tree. In the likely event that the indri goes extinct, we will lose 19m years of unique evolutionary history from the mammal tree of life. (Photo by Pierre-Yves Babelon/Aarhus University)