Soviet Army soldiers sit on their tanks in front of the Czechoslovak Radio station building in central Prague during the first day of Soviet-led invasion to then Czechoslovakia on August 21, 1968. (Photo by Libor Hajsky/Reuters)

Italian disabled dancer Simona Atzori (top) performs, before a special audience with disabled athletes led by Pope Francis, in Paul VI hall at the Vatican October 4, 2014. (Photo by Tony Gentile/Reuters)

Demi Rose attends Sixty6 Magazine – issue two launch party at Paper club on March 22, 2017 in London, England. (Photo by Splash News and Pictures)

Police react to a suspicious vehicle near La Carillon restaurant following a series of deadly attacks in Paris, November 15, 2015. Thousands of French troops deployed around Paris on Sunday and tourist sites stood shuttered in one of the most visited cities on Earth while investigators questioned the relatives of a suspected suicide bomber involved in the country's deadliest violence since World War II. (Photo by Pascal Rossignol/Reuters)

Poland's Dawid Kubacki soars through the air during the men's FIS Ski Jumping World Cup competition in Engelberg, central Switzerland, on December 20, 2014. (Photo by Fabrice Coffrini/AFP Photo)

A participant in the 5th Lady on Bicycle annual festival opens her bag in the back basket of her tricycle in the Sokolniki park in Moscow on August 6, 2017. The festival's aim is to capture the city's fashionable women on vintage style bicycles. (Photo by Mladen Antonov/AFP Photo)

A Haitian woman lies in a trance during a voodoo ceremony in Souvenance, a suburb of Gonaives, 171 km north of Port- au- Prince, on April 16, 2017. Haitian voodoo followers arrived in Souvenance to take part in the voodoo ceremonies held during Easter weekend. (Photo by Hector Retamal/AFP Photo)

An image produced by the Hubble telescope of the perfectly “edge-on” galaxy, or NGC 4013, March 1, 2001. This new Hubble picture reveals, with great detail, huge clouds of dust and gas extending along, as well as far above, the galaxy's main disk. NGC 4013 is a spiral galaxy, similar to the Milky Way, lying some 55 million light-years from Earth in the direction of the constellation Ursa Major. Viewed face-on, it would look like a nearly circular pinwheel, but NGC 4013 happens to be seen edge-on from our vantage point. Even at 55 million light-years, the galaxy is larger than Hubble's field of view, and the image shows only a little more than half of the object, albeit with unprecedented detail. (Photo Courtesy of NASA/Newsmakers)