A man passes by an unfinished street art graffiti made in a stairway by French street artists Zag and Sia in Paris on March 1, 2016. The two artists drew inspiration from famous “Liberty Leading the People” (La Liberte guidant le peuple) painting by French Eugene Delacroix commemorating the July Revolution of 1830 and viewed as a symbol of the French Republic. (Photo by Joel Saget/AFP Photo)

“Rudolf Khametovich Nureyev was a Russian Tatar dancer from the former Soviet Union, primarily known for his work in ballet. Nureyev's artistic skills explored expressive areas of the dance, providing a new role to the male ballet dancer who once served only as support to the women. He defected to the West, despite KGB efforts to stop him. According to KGB archives studied by Peter Watson, Nikita Khrushchev personally signed an order to have Nureyev killed”.

Photo: British ballerina Margot Fonteyn (Margaret Hookham) (1919 – 1991) and her professional partner during his tenure with the Royal Ballet Rudolf Nureyev. (Photo by Potter/Express/Getty Images). 12th December 1965. (Photo by Central Press/Getty Images)

“Echus Chasma is a chasma in the Lunae Planum high plateau north of the Valles Marineris canyon system of Mars. Clay has been found in Echus Chasma that means that water once sat there for a time. Echus Chasma is approximately 100 km long and 10 km wide, with valleys ranging in depth from around 1 km to 4 km”. – Wikipedia

Photo: In this handout image supplied by the European Space Agency (ESA) on July 16, 2008, The Echus Chasma, one of the largest water source regions on Mars, is pictured from ESA's Mars Express. The data was acquired on September 25, 2005. The dark material shows a network of light-coloured, incised valleys that look similar to drainage networks known on Earth. It is still debated whether the valleys originate from precipitation, groundwater springs or liquid or magma flows on the surface. (Photo by ESA via Getty Images)

Afghan girl athletes perform Wushu on the top of a hill in Kabul, capital of Afghanistan, January 18, 2017. In the conservative Afghan society where people especially in the countryside deeply believe in the old traditions and don't allow their girls and female members of the family to go out of home, exercising sport in open is extremely risky, but a group of girls are broken the taboo and exercising Wushu on a hilltop where the temperature is minus 2 Celsius degrees. (Photo by Rahmat Alizadah/Xinhua/Barcroft Images)

A traditional Russian nesting doll painted with the likeness of President of Donald Trump and his family is displayed for sale at a Moscow store on March 5, 2017 in Moscow, Russia. Relations between the United States and Russia are at their lowest point in years as evidence mounts about the complex relationship between President Donald Trump's administration and the Russian government. (Photo by Spencer Platt/Getty Images)

Students participate in a wet t-shirt contest at the MTV Beach Bash party put on by Global Groove at the Bahia Mar Hotel during the annual ritual of Spring Break March 26, 2008 on South Padre Island, Texas. The South Texas island is one of the top Spring Break destinations and attracts students from all over the country. (Photo by Rick Gershon/Getty Images)

Attendees look at Volkswagen's BUDD-e, a long distance electric vehicle, displayed during a press event at CES 2016 at The Chelsea at The Cosmopolitan of Las Vegas on January 5, 2016 in Las Vegas, Nevada. CES, the world's largest annual consumer technology trade show, runs from January 6-9 and is expected to feature 3,600 exhibitors showing off their latest products and services to more than 150,000 attendees. (Photo by David Becker/Getty Images)

Up to 35% of Mongolians still live a nomadic life, depending on their land to survive. But environmental changes, particularly desertification, means this way of life is under threat. Korean photographer Daesung Lee’s Futuristic Archaeology images show billboard-size backdrops of lush steppe contrasting with actual scenery as former nomads enact scenes of hunting, herding and Mongolian wrestling. (Photo by Daesung Lee)