The competition, which is run by the Royal Observatory Greenwich in association with BBC Sky at Night Magazine, is now in its sixth year and has received over 2,500 entries. Photo: Centre of the Heart Nebula by Ivan Eder (Hungary). Situated 7500 light years away in the “W”-shaped constellation of Cassiopeia, the Heart Nebula is a vast region of glowing gas, energized by a cluster of young stars at its centre. The image depicts the central region, where dust clouds are being eroded and moulded into rugged shapes by the searing cosmic radiation. (Photo by Ivan Eder)

Flames from a burning barricade lit by pro-democracy protesters is reflected in the windows of a passing bus as passengers watch on during a protest gathering in front of Mong Kok police station on September 22, 2019 in Hong Kong, China. Pro-democracy protesters have continued demonstrations across Hong Kong, calling for the city's Chief Executive Carrie Lam to immediately meet the rest of their demands, including an independent inquiry into police brutality, the retraction of the word “riot” to describe the rallies, and genuine universal suffrage, as the territory faces a leadership crisis. (Photo by Chris McGrath/Getty Images)

In this April 20, 2018, file aerial photo released by China's Xinhua News Agency, advection fog drifts across skyscrapers on the waterfront in Qingdao in eastern China's Shandong Province. Chinese leaders have long been sensitive about their communist country’s international image. Now, they are battling back, investing in diplomacy and a courtship of hearts and minds, just as the United States digs in on the Trump administration’s “America First” mindset. (Photo by Lu Hui/Xinhua via AP Photo/File)

Napoli fans celebrate after winning the Coppa Italia final against Juventus FC, in central Naples, Italy on June 17, 2020. Napoli won the Italian Cup with a 4-2 penalty shootout victory over Juventus following a 0-0 draw in a match played at the Rome Olympic Stadium. (Photo by Salvatore Laporta/IPA/Rex Features/Shutterstock)

A fox runs out onto the pitch before the start of the second half. Celtic League 2012/13, Round 19, Leinster v Ulster, RDS, Ballsbridge, Dublin, March 30, 2013. (Photo by Paul Mohan)

A four-month-old snow fox cub named “Vesna” (“Spring”) leaps next to a Zoo employee at the Royev Ruchey Zoo in Krasnoyarsk, Russia, on August 6, 2013. (Photo by Ilya Naymushin/Reuters)

Polish police in riot gear detain protesters, angry over new restrictions aimed at fighting the coronavirus pandemic, in Warsaw, Poland, Saturday, October 24, 2020. The protesters included entrepreneurs, far-right politicians, football fans and vaccine opponents. The clashes come amid rising social tensions and as new restrictions just short of a full lockdown took effect Saturday. (Photo by Czarek Sokolowski/AP Photo)

Motorcycle enthusiast Gilbert Delos Reyes rides with his pet dog Bogie, in Kawit, Cavite, Philippines, November 26, 2020. (Photo by Eloisa Lopez/Reuters)