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 participant in the 5th Lady on Bicycle annual festival opens her bag in the back basket of her tricycle in the Sokolniki park in Moscow on August 6, 2017. The festival's aim is to capture the city's fashionable women on vintage style bicycles. (Photo by Mladen Antonov/AFP Photo)

Svetlana Tseyko feeds a 10-month-old moose named Grisha in the courtyard in the village of Abramy, some 160 km northwest of Minsk, on February 21, 2017. (Photo by Sergei Gapon/AFP Photo)

A Palestinian woman takes a picture of a member of the Israeli security forces as he takes her picture in a street in Jerusalem on December 16, 2017, as demonstrations continue to flare in the Middle East and elsewhere over the US president' s declaration of Jerusalem as Israel' s capital. (Photo by Ahmad Gharabli/AFP Photo)

Food affected villagers cross flood waters through a bamboo bridge in the flood affected Morigaon district of Assam state, India, 05 July 2016. Continuous rain since last couple of days inundated six districts of Assam effecting more than 100 thousand people in the second wave of floods in Assam state. (Photo by EPA/Stringer)

Rescue workers stand next to TK Bremen cargo ship which ran aground during a powerful storm, spilling oil off the coast of France's northwestern region of Brittany as it lies stranded on Kerminihy beach in Erdeven, on December 16, 2011. (Photo by Damien Meyer/AFP Photo)

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

A sewer cleaner of Dhaka City Corporation cleaning out the city's sewers on May 03, 2017 in Dhaka, Bangladesh. Despite a rise in the number of deaths of manhole workers every year, workers regularly go into the manholes without any protective gear. (Photo by Zakir Chowdhury/Barcroft Images)