Armed man stand at entrance of the naval headquarters in Sevastopol, March 19, 2014. Around a dozen Ukrainian servicemen, unarmed and in civilian clothes, walked out of the Ukrainian naval headquarters in the Crimean port of Sevastopol on Wednesday after it was taken over by pro-Russian forces, a Reuters witness said. (Photo by Baz Ratner/Reuters)

“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)

Williams Formula One driver Felipe Massa of Brazil crashes with his car in the first corner after the start of the German F1 Grand Prix at the Hockenheim racing circuit, July 20, 2014. (Photo by Kai Pfaffenbach/Reuters)

This picture taken on July 25, 2014 shows people cooling off in a waterpark in Suining, southwest China's Sichuan province. Meteorological departments issued an orange alert for high temperature as a heat wave embraces Sichuan province, with temperature of most area topped 37, local media reported. (Photo by AFP Photo)

A Rohingya Muslim from Myanmar (R), who tried to cross the Naf river into Bangladesh to escape sectarian violence, cries near his family in a Bangladeshi Coast guard station in Teknaf on June 19, 2012, before being sent back to Myanmar. (Photo by Munir Uz Zaman/AFP Photo)

Austrian alpine skiers (LtoR) Georg Streitberger, Klaus Kroell, Max Franz, Joachim Puchner, Romed Baumann pose in the Olympic Rings on February 4, 2014 at the Mountain Olympic Village at the Rosa Khutor Alpine centre, four days prior to the start of the 2014 Sochi Winter Olympic Games. (Photo by Fabrice Coffrini/AFP Photo)

An American flag is visible in the windows of the cupola aboard the International Space Station. Thanks to a bill passed by Texas legislators in 1997 that put in place technical voting procedure for astronauts – nearly all of whom live in Texas – they have the ability to vote from space through specially designed absentee ballots. To preserve the integrity of the secret vote, the ballot is encrypted and only accessible by the astronaut and the county clerk responsible for casting the ballot. (Photo by NASA)

A Pakistani farmer guides his bulls as he competes in a traditional bull race in Khunda village in the northwestern district of Attock, some 80 kilometers from Islamabad on January 3, 2015. Tens of thousands of people gather whenever there is a bull race held in Pakistan which are usually the highlight of festivals organized in rural areas of the Asian country, and attract lots of spectators due to their thrilling nature. The traditional competition attracts landlords and farmers from all around the province where the race is held, and they all bring their fastest and strongest bulls in hopes of gaining a reputation. (Photo by Aamir Qureshi/AFP Photo)