New York City policemen tangled with demonstrators at a subway station on the opening day of the New York World's Fair, April 22, 1964. Youths attempted to stall the train, which was headed from the city to the fairgrounds, as a form of protest on behalf of civil rights for blacks. (Photo by Charles Gorry/AP Photo)

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)

“Show us our butts! Mucawana tribe – Angola. In Soba village, the Muhacaona (Mucawana) tribe, perhaps the best place i have visited. They use cow dung and fat to make this so nice haircut, and love the beads. They asked me to make pictures of their backs... and butts to see on the camera screen if everything was perfect!”. (Photo and comments by Eric Lafforgue)

With the humpback calving season drawing to a close, here’s a look at some of Rita Kluge’s distinctive marine photos from the south Pacific. The Sydney-based photographer fell in love with whales after witnessing southern rights from the New South Wales coastline as they travelled to and from their feeding grounds in the Antarctic. She has since been to Tonga, where humpbacks breed and calf in winter months, to photograph them in the water. (Photo by Rita Kluge/The Guardian)

Office sеx. (Photo by Orange-Melody/Getty Images)

This is the mesmerising image of a colourful Milky Way shining down on Mount Fuji. Steve Lance Lee, 37, captured the sky above the iconic mountain whilst on his honey moon in Lake Kawaguchiko, Japan. Mount Fuji is illuminated underneath the galaxy of stars, creating an impressive landscape. Here: The beautiful image captured by Steve Lance Lee of the Milky Way seemingly errupting from Mt. Fuji in Japan. (Photo by Steve Lance Lee/Caters News)

Its your big day, youve spent months planning every last detail of your wedding and youre just about to capture the moment perfectly on camera whenyoure upstaged by a grinning donkey. At least thats what happened to these poor couples who were dramatically photobombed by a whole host of camera-hogging animals on their special day.The hilarious snaps show a series of irate brides being upstaged by everything from a cat to a camel and a dog to a donkey. Here: A donkey photobombs a bride on her wedding day. (Photo by Caters News Agency)

A boat sails behind a woman looking through binoculars as she sits on a cliff on a sunny day in Sydney, Australia, May 29, 2016. (Photo by David Gray/Reuters)