Libyan leader Muammar Gaddafi attends the inauguration ceremony of Jacob Zuma on May 9, 2009 in Pretoria, South Africa. Jacob Gedleyihlekisa Zuma is South Africa's fourth President since the end of apartheid. (Photo by Foto24/Gallo Images/Getty Images)

Protesting university students flee as police fire stun grenades outside Parliament in Cape Town, South Africa, Wednesday October 21, 2015. The protests are part of a wave of nationwide protests that have shut down many South Africa universities, which say they are struggling with higher operational costs as well as inadequate state subsidies. (Photo by AP Photo)

Children react as they celebrate Guy Fawkes day in Soweto, South Africa, on November 5, 2014. (Photo by Siphiwe Sibeko/Reuters)

A man takes a picture of sea spray as storms hit Cape Town, South Africa, June 7, 2017. (Photo by Mike Hutchings/Reuters)

Open jaws of a Great White Shark Carcharodon Carcharias, South Africa. (Photo by Stephen Frink Collection/Alamy Stock Photo)

A hyena cub got a mouthful from his mum after it appears he got a right telling off. Michael Raddall, a animal enthusiast and wildlife photographer from South Africa, snapped the mum and cub at the Timbavati game reserve in South Africa while on safari at the Umlani Bush camp. (Photo by Michael Raddall/Caters News Agency)

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.