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)

Now celebrating its 40th year, Nikon Small World is widely regarded as the leading forum to recognize proficiency and photographic excellence of photography taken under the microscope. To select the winners, competition judges analyzed entries from all over the world covering subjects ranging from chemical compounds to up-close-and-personal looks at biological specimens. The 2014 winners will be revealed on October 30th. In 2014, the competition received over 1,200 entries from more than 79 countries around the world. (Photo by Dr. Igor Robert Siwanowicz/Nikon Small World 2014)

People fight for the ball as they take part in a mud football match during a festival for celebrating harvest in a village in Jinhua, Zhejiang Province, China September 24, 2017. (Photo by Reuters/China Stringer Network)

Yippie leader Jerry Rubin, barred on December 4, from House Un-American Activities subcommittee hearing, aims a toy gun in “self defense” outside the Washington hearing room on December 5, 1969. Rubin showed up in his Santa Clause suit because he believed it was typical of the committee which, he said, “is a total circus”. (Photo by Bob Daugherty/AP Photo)

NASA's new moon rocket lifts off from the Kennedy Space Center in Cape Canaveral, Wednesday morning, November 16, 2022, as seen from Harbor town Marina on Merritt Island, Fla. The moon is visible in the sky. (Photo by Malcolm Denemark/Florida Today via AP Photo)

Soldiers from the Nigerian Armed Forces take position and secure the streets in Lagos Island, Lagos, on February 27, 2023, after hoodlums had harassed market owners. Nigeria slowly counted more results on Monday after a tight election for the presidency of Africa's most populous nation as delays and accusations of manipulation fuelled tensions Nearly 90 million were eligible to vote on Saturday for a successor to President Muhammadu Buhari, with many hoping for a new leader to tackle insecurity, economic malaise and widening poverty. (Photo by John Wessels/AFP Photo)

A Kashmiri Muslim girl reacts to camera as she attends recitation classes of the holy Quran during the fasting month of Ramadan in Srinagar, Indian controlled Kashmir, Sunday, March 26, 2023. Muslims across the world are observing the holy fasting month of Ramadan, where they refrain from eating, drinking and smoking from dawn to dusk. (Photo by Mukhtar Khan/AP Photo)

People enjoy their time during the last day of the Dubai Expo 2020 in Dubai, United Arab Emirates, Thursday, March 31, 2022. The world's fair in Dubai, the pandemic-delayed Expo 2020, closed on Thursday after six months of concerts, conferences and festivities. (Photo by Ebrahim Noroozi/AP Photo)