Amundsen-Scott South Pole Station experiences months of darkness. The sun dips below the horizon on March 21, after which follows several weeks of twilight before complete darkness results. Photo taken on June 25, 2009. (National Science Foundation/Jeremy Johnson)

“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)

The lead singer of one band talks to two bemused kids at a gig at the “Warzone Centre” in Belfast, Northern Ireland, 1980s. (Photo by Ricky Adam/Mediadrumworld)

A Libyan fireman stands in front of smoke and flames rising from an oil storage tank at an oil facility in northern Libya's Ras Lanouf region on January 23, 2016, after it was set ablaze earlier in the week following attacks launched by Islamic State (IS) group jihadists to seize key port terminals. (Photo by AFP Photo/Stringer)

Tyson the Bulldog sits with reindeer antlers on Christmas Day at Central Park in Manhattan, New York City, U.S., December 25, 2016. (Photo by Andrew Kelly/Reuters)

Members of the San Francisco Gay Freedom Day Marching Band and Twirling Corps do their thing down San Francisco's Market Street, June 27, 1982. Police estimate the crowd to be 300,000 for the Lesbian/Gay Freedom Day parade and rally. (Photo by Carl Viti/AP Photo)

Victorious in 129 successive fights, including 40 as a pro, Ray Robinson falls through the ropes of a ring, under the impact of Jake LaMotta's fists on Olympia Stadium, Detroit, Michigan on February 5, 1943. Robinson got back in the ring, but lost the decision in ten rounds. LaMotta pummelled him for the rest of the fight, winning via a unanimous decision, giving Robinson the first defeat of his career.They fought again just 21 days later when Robinson regained his mantle winning in another 10-round fight, Robinson won the close fight by a unanimous decision. LaMotta stated the bout was gifted to Robinson because he would be inducted into the army the next day. (Photo by Bettmann Archive/Getty Images)

In this October 15, 2014 file photo, Katsu Nakamura, sky division manager for Yamaha USA, moves the RMax unmanned helicopter into position before a demonstration of its aerial application capabilities at the University of California, Davis' Oakville Station test vineyard in Oakville, Calif. Researchers at UC Davis have been studying the effectiveness of the drone's ability for spraying pest control and nutritional materials on the test vineyard in California's Napa Valley. (Photo by Rich Pedroncelli/AP Photo)