Soviet cosmonaut and the first man to travel in space, Yury Alekseyvich Gagarin (1934–1968) arriving in London for a Russian trade fair. (Photo by Douglas Miller/Getty Images)

Gunfire erupted at a Denver pot celebration Saturday, injuring two people and scattering a crowd of thousands who had gathered for the first 4/20 counterculture holiday since the state legalized marijuana... Photo: A woman smokes a large marijuana joint at the Vancouver Art Gallery during the annual 4/20 day, which promotes the use of marijuana, in Vancouver, British Columbia April 20, 2013. (Photo by Ben Nelms/Reuters)

People look at a tanker after it fell into a caved-in area on a road in Xi'an, Shaanxi province, July 27, 2013. No casualty was reported in the accident, according to local media. (Photo by Reuters/Stringer)

Norma Galicia aka “Pirulina” takes part in a demonstration during the commemoration of the International Day for the Elimination of Violence Against Women, in Guatemala City on November 25, 2013. So far this year, 696 women have died due to violent events in Guatemala. (Photo by Johan Ordonez/AFP Photo)

A mine detection rat is given banana as a reward after successfully identifying an inactive mine on July 2, 2015 in Siem Reap, Cambodia. The Cambodian Mine Action Center (CMAC) working with the Belgian NGO APOPO has recently begun testing the feasability of using large mine detection rats from Tanzania to help clear fields of mines and unexploded ordnance in one of the most bombed and mined countries in the world. (Photo by Taylor Weidman/Getty Images)

In this photo provided by Jean Revillard, Solar Impulse 2, a plane powered by the sun's rays and piloted by Andre Borschberg, approaches Kalaeloa Airport near Honolulu, Friday, July 3, 2015. His 120-hour voyage from Nagoya, Japan broke the record for the world's longest nonstop solo flight, his team said. (Photo by Jean Revillard/Global Newsroom via AP Photo)

Young women prepare for Notting Hill Carnival on August 27, 2017 in London, England. The Notting Hill Carnival began with a special ceremony of remembrance following the Grenfell fire tragedy. (Photo by Leon Neal/Getty Images)

In this photo taken on August 26, 2017, a contestant of the “fantasy” category prepares to be judged during the Daegu International Bodypainting Festival in Daegu, South Korea. The bodies of dozens of female models turned into living canvases this weekend as they allowed delicate brush strokes and flamboyant illustrations to cover up their bare skin. They are part of the 2017 Daegu International Bodypainting Festival along with top artists from 10 countries that runs until August 27 in South Korea's southeastern city of Daegu. (Photo by Ed Jones/AFP Photo)