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)

A doorman stands at the entrance of the “The Walled Off Hotel” in the West Bank city of Bethlehem, Friday, March 3, 2017. The owner of a guest house packed with the elusive artist Banksy's work has opened the doors of his West Bank establishments to media, showcasing its unique “worst view in the world”. The hotel, several of whose rooms look onto an Israeli security watchtower, is awash in the trademark satirical work of the mysterious artist. (Photo by Dusan Vranic/AP Photo)

Two cats watch a mouse walking on the pavement in Kuwait City on March 8,2017. (Photo by Yasser Al-Zayyat/AFP Photo)

An Iranian Shiite Muslim prays in Laylat al-Qadr, or the night of destiny, during holy fasting month of Ramadan after midnight, in central Tehran, Iran, early Sunday, June 18, 2017. Laylat al-Qadr is the night when Muslims believe the Quran was first revealed to prophet Muhammad. Worshipers gather in religious ceremonies to pray, ask forgiveness and make wishes on one of the most important nights of the Islamic calendar. Shiite Muslims, the vast majority of Iranians, believe the night happens either on 19th, 21st or 23rd of the holy month of Ramadan. (Photo by Ebrahim Noroozi/AP Photo)

Luling, Louisiana, US. New evidence contradicts previous claims of the relative safety of glyphosate, the world’s most widely used herbicide, which is manufactured here. It is often used in conjunction with seeds that have been genetically modified to tolerate its application, meaning that anyone consuming these crops is eating a genetically modified plant, and whatever residue of the pesticide that remains. (Photo by J. Henry Fair/Industrial Scars/Papadakis Publisher)

Carine Louis-Jean, 22, poses for a photograph in her destroyed house after Hurricane Matthew hit Jeremie, Haiti, October 17, 2016. “The roof of my house is completely gone and some of walls were destroyed. I have lost everything I had, but I thank God that I have a friend who is letting me stay at her house. I could say I'm lucky, because none of my family died during the hurricane, but I do not think I'm lucky”, said Louis-Jean. (Photo by Carlos Garcia Rawlins/Reuters)

In this picture taken Thursday, August 4, 2016, seal Tristan looks out of a basket while being released into the North Sea together with others at the beach of the island Juist, Germany. He is part of the first group of released seals of the seal breeding station Norddeich this year. (Photo by Carmen Jaspersen/DPA via AP Photo)

Maja, a 40-year-old elephant, extends her trunk into a bakery as a customer buys a newspaper while Maja took a stroll through the neighborhood with her minders from a nearby circus on July 1, 2016 in Berlin, Germany. (Photo by Sean Gallup/Getty Images)