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 dressed in folk costumes take part in a traditional wedding ceremony in the village of Galicnik, west of Macedonia's capital Skopje, July 12, 2014. The Galicnik Wedding, a three-day traditional Macedonian wedding celebration held each “Petrovden” or St. Peter's Day, involves traditional customs, costumes, and rituals and dances that have been passed down over the centuries. (Photo by Ognen Teofilovski/Reuters)

Children with painted faces in the art of the bahurupi tradition in Bardhaman, India on April 24, 2021. Impersonators family where their generations are engaged in making face painting and can easily metamorphose into different characters during a performance, as per different Traditional & Tribal myth which is the main earning source for their family. (Photo by Avishek Das/SOPA Images/Rex Features/Shutterstock)

A South Korea university student gets her head shaved during a protest against Japan's decision to release contaminated water from its crippled Fukushima nuclear plant into the sea, in front of the Japanese embassy, in Seoul, South Korea, April 20, 2021. (Photo by Kim Hong-ji/Reuters)

A young girl splashes through a waterfall at a park in Washington, DC, on June 28, 2021, as a heatwave moves over much of the United States. Swathes of the United States and Canada endured record-setting heat on June 27, 2021, forcing schools and Covid-19 testing centers to close and the postponement of an Olympic athletics qualifying event, with forecasters warning of worse to come. The village of Lytton in British Columbia broke the record for Canada's all-time high, with a temperature of 46.6 degrees Celsius (116 Fahrenheit), said Environment Canada. (Photo by Jim Watson/AFP Photo)

A confiscated pet lion poses with a dog as it arrived back home from the Phnom Tamao Wildlife Rescue Center after Prime Minister Hun Sen ordered authorities to return the animal in Phnom Penh, Cambodia, July 5, 2021. (Photo by Cindy Liu/Reuters)

A child prays in front of the cenotaph dedicated to the victims of the atomic bombing at the Hiroshima Peace Memorial Park in Hiroshima, western Japan Friday, August 6, 2021. Hiroshima on Friday marked the 76th anniversary of the world's first atomic bombing of the city. (Photo by Kyodo News via AP Photo)

This picture taken on September 9, 2021 and released from North Korea's official Korean Central News Agency (KCNA) shows a parade of “paramilitary and public security forces” to celebrate the 73rd founding anniversary of North Korea at Kim Il Sung Square in Pyongyang. (Photo by KCNA via KNS/AFP Photo/Stringer)