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)

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)

Women jump into the water during a traditional New Year bath in the Adriatic sea in Portoroz, Slovenia on January 1, 2018. (Photo by Jure Makovec/AFP Photo)

In this Thursday, May 16, 2013 file photo, Finland's Krista Siegfrids, second right, kisses a dancer as she performs her song “Marry Me” during the second semifinal of the Eurovision Song Contest at the Malmo Arena in Malmo, Sweden. That was the first girl-on-girl kiss in the history of the annual competition. Previously, organizers had sought to prevent similar embraces citing the competition's status as a family event. (Photo by Alastair Grant/AP Photo)

2016 Rio Olympics, Weightlifting, Final, Women's 69kg, Riocentro, Pavilion 2, Rio de Janeiro, Brazil on August 10, 2016. Leidy Solis (COL) of Colombia competes. (Photo by Stoyan Nenov/Reuters)

Yamaha Spanish rider Alex Rins falls during the MotoGP sprint race of the Portuguese Grand Prix at the Algarve International Circuit in Portimao on March 23, 2024. (Photo by Patrícia de Melo Moreira/AFP Photo)

A participant in the “Cats Who Look Like Cows” competition wears a cowboy outfit back stage before judging on March 05, 2023 in Bangkok, Thailand. Thailand's Cat Fanciers' Club hosted a “Cats Who Look Like Cows” competition during a Cat Expo in Bangkok's Ladphro neighborhood. Over 100 cats were judged on how similarly their pattern resembled a cow, color, fur softness and personality. A relaxed, fluffy cat named Arpo took home first prize. (Photo by Lauren DeCicca/Getty Images)

A participant holds his dog as colored powder is thrown into the air during the Color Run in Lausanne, Switzerland, 12 September 2015. The international 5km running event is inspired by the Hindu Holi spring festival of colors. (Photo by Valentin Flauraud/EPA)