Brazilian graffiti artist Eduardo Kobra (C) puts the final touches to his piece of art in tribute to Brazilian architect Oscar Niemeyer, next to his assistants, at the financial center on Sao Paulo's Avenida Paulista January 22, 2013. Kobra created the 56-metre (61-yard) tall graffiti artwork as a tribute to Niemeyer, one of the 20th century's most influential modernist architects. Niemeyer died in December 2012, aged 104. (Photo by Andre Penner/AP Photo)

A christmas teddy bear is wheeled along on a trolley at the Steiff stuffed toy factory on November 23, 2012 in Giengen an der Brenz, Germany. Founded by seamstress Margarethe Steiff in 1880, Steiff has been making stuffed teddy bears since the early 20th century ever since her nephew Richard Steiff exhibited the first commercially produced teddy bear in Europe in 1903. Teddy bears are among the most popular children's toys and the company is hoping for a strong Christmas season. (Photo by Thomas Niedermueller)

Two Teddy Bears from the 1920's sit on display in the museum section of the Merrythought Teddy Bear shop on April 5, 2011 in Ironbridge, England. Established in 1930, Merrythought has been hand-making Teddy Bears for over 80 years in Shropshire. The family-run company is the last remaining British teddy bear factory and is launching its latest limited edition bear to mark the royal wedding. The Commemorative Royal Wedding bear is limited to 75 and comes after its popular Prince William and Catherine Middleton bears completely sold out. Merrythought has also been selected by the London Olympic Games organisers to produce the official teddy bears of the London 2012 Olympic and Paralympic games. (Photo by Christopher Furlong/Getty Images)

Crowds wave as HMS Daring, the largest and most powerful destroyer warship ever built for the Royal Navy, leaves Portsmouth Harbour on January 11, 2012 in Portsmouth, England. HMS Daring, the first of six new Type 45 destroyers embarked from Portsmouth on its maiden deployment, a seven-month mission to the Middle East. (Photo by Matt Cardy/Getty Images)

A plane passes the Full moon as it rises over Albert Bridge on February 7, 2012 in London, England. Albert Bridge is said to be one of the most romantic bridges in London, and will be the start point for the flotilla of boats that will make their way along the Thames as part of the Queen's Diamond Jubilee celebration. (Photo by Dan Kitwood/Getty Images)

Sandrine Kerfante has had a fascination with “doubles” ever since meeting her mother’s twin as a child. In 2012, this lifelong captivation inspired her to create a blog called twin-niwt, which celebrates photographs of doubles in all their forms. “I’m fascinated by the idea of the duo, repetition, symmetry, reflection, mirror games and all the symbolism associated with it”, she says. “I think it’s a topic often present in photography, more or less consciously”. (Photo by Sandrine Kerfante/The Guardian)

This artist's scoreboard displays a fictional game between Mars and Earth, with Mars in the lead. It refers to the success rate of sending missions to Mars, both as orbiters and landers. Of the previous 39 missions targeted for Mars from around the world, 15 have been successes and 24 failures. For baseball fans, that's a batting average of .385. The United States has had 13 successes out of 18 attempts, or a “batting average” of .722. NASA's Curiosity rover, set to land on the Red Planet the evening of Aug. 5, 2012 PDT (morning of Aug. 6 EDT), will mark the United States' 19th attempt to tackle the challenge of Mars, and the world's 40th attempt. (Image by NASA/JPL-Caltech)

Retired builder Vasili Sidamonidze, 70, poses for a portrait at his home in Gori, Georgia, December 6, 2016. “Unfortunately, Stalin is not popular nowadays. Our people don't respect him. Only we, members of the (Communist) Party, respect him”, Sidamonidze said. “I always try to attend Stalin's birthday anniversaries in Gori. Unfortunately many people don't want to join us even if they live nearby. They look at us from their windows”. (Photo by David Mdzinarishvili/Reuters)