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)

Amundsen-Scott South Pole Station experiences months of darkness. The sun dips below the horizon on March 21, after which follows several weeks of twilight before complete darkness results. Photo taken on June 25, 2009. (National Science Foundation/Jeremy Johnson)

Members of the Communist New Fourth Army on parade. Note how the modern equipment contrasts with the shoeless soldiers in the foreground. (Photo by Hulton Archive/Getty Images). 6th July 1946

A student from the General Yermolov Cadet School performs with models of swords during celebrations of Maslenitsa, or Pancake Week, a pagan holiday marking the end of winter, in southern city of Stavropol, Russia, March 6, 2019. (Photo by Eduard Korniyenko/Reuters)

Celebrities Switch into their 2nd Outfits for the Met Gala After Parties on May 7, 2019. Pictured: Hailey Bieber. (Photo by DIGGZY/Splash News and Pictures)

Model Elise Daniels dons a Balenciaga suit while surrounded by street performers in Paris, France in 1948. (Photo by Richard Avedon/Victoria and Albert Museum London/The Guardian)

In this July 20, 2019 photo, children play during a sports event organized by members of the Caracas FC soccer club, in Catia, one of the poorest slums in Caracas, Venezuela. When the Caracas Football Club plays, its supporters leave their ideological preferences and socioeconomic differences behind, joining together to support and take care of each other inside and outside the stadium. (Photo by Matias Delacroix/AP Photo)

A general view of Copacabana beach during the coronavirus disease (COVID-19) outbreak in Rio de Janeiro, Brazil, March 22, 2020. (Photo by Ricardo Moraes/Reuters)