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)

An employee of the National Park Service takes a selfie with President Barack Obama, left, in the background meeting with the crowd after a tour of Everglades National Park on Earth Day, Wednesday, April 22, 2015, in Florida. Obama used the visit to warn of the damage that climate change is already inflicting on the nation's environmental treasures. (Photo by Lynne Sladky/AP Photo)

A photograph made available on 02 October 2016 showing Indian people dressed in traditional attire performing the Garba dance, a ritual performed to appease Goddess Durga, in a religious event named, “Abhivyakti 2016” during the nine-day long Navratri festival in Bhopal, India, 01 October 2016 Celebrated twice a year during the spring and the fall season, the Navratri festival is dedicated to the Hindu Goddess Durga. (Photo by Sanjeev Gupta/EPA)

A vehicle leaves light trails in a long exposure photograph as it drives beneath the 500-metre Aperture Spherical Radio Telescope in Pingtang county, China. Construction on the device began in 2011 and is nearing completion. (Photo by Liu Xu/AP Photo)

A boy and a serviceman pose for a picture during Marines Day celebration in the Black Sea port of Sevastopol, Crimea, November 27, 2016. (Photo by Pavel Rebrov/Reuters)

Blindfolded Myanmar boys try to eat the biscuits during a fair on the occasion of the 73rd Myanmar Independence Day in Yangon, Myanmar, 04 January 2021. Myanmar, also known as Burma, was colonized by Britain in 1824 and became an independent republic on 04 January 1948. (Photo by Lynn Bo Bo/EPA/EFE)

Gigi Hadid, American fashion designer Jeremy Scott and Bella Hadid pose backstage of the Moschino fashion show during the Milan Fashion Week Fall/Winter 2022/2023 on February 24, 2022 in Milan, Italy. (Photo by Vittorio Zunino Celotto/Getty Images)

Gong Yan of Team China flies out of the gate at the Para Alpine Skiing Men's Super Combined Super-G Standing at Yanqing National Alpine Skiing Centre during day three of the Beijing 2022 Winter Paralympics on March 07, 2022 in Yanqing, China. (Photo by Joel Marklund for OIS/PA Wire)