Harris & Ewing Inc. photographed people, events, and architecture, particularly in Washington, D.C., during the period 1905-1945. Photo: Tests of Curtiss Palne for Army, Single Control. Created by Harris & Ewing. Published in 1912.

This image is NGC 6543 known as the Cat's Eye Nebula as it appears to the Chandra X-Ray Observatory and Hubble Telescope. A planetary nebula is a phase of stellar evolution that the sun should experience several billion years from now, when it expands to become a red giant and then sheds most of its outer layers, leaving behind a hot core that contracts to form a dense white dwarf star. This image was released October 10, 2012. (Photo by J. Kastner/NASA/CXC/RIT)

Men dressed as soldiers pose with models before the opening of the Gamescom 2013 fair in Cologne,Germany, on August 23, 2013. The Gamescom convention is Europe's largest video games trade fair. (Photo by Ina Fassbender/Reuters)

Two women pose as they drink real ale at the Great British Beer Festival in the Olympia exhibition centre on August 13, 2013 in London, England. The festival, which runs until August 17, 2013, has over 24 bars serving over 800 different beers, ciders and perries. (Photo by Oli Scarff)

A silicon rug in the form of Adolph Hitler on display during an exhibition by Israeli artist Boaz Arad, at the Center for Contemporary Art February 22, 2007 in Tel Aviv, Israel. Arad is an Israeli artist who is dealing with the Holocaust in a provocative way. He uses the Holocaust to discuss human evil and contemporary Israel, which he says is torn and crumbling. (Photo by David Silverman/Getty Images)

A boy dressed as Hindu Lord Shiva poses before performing in a religious procession at the Mahashivratri festival in Allahabad, India, March 7, 2016. Hindus across the country celebrate Mahashivratri, better known as Lord Shiva's wedding anniversary. (Photo by Jitendra Prakash/Reuters)

Palestinian woman Jihan Abu Muhsen prepares her donkey with her son Kareem before going work collecting bricks for sale from sites of demolished buildings, at her dwelling in Khan Younis in the southern Gaza Strip March 8, 2016. Abu Muhsen gathers bricks from the sites of demolished buildings and sells them to recycling factories. She earns around 20 shekels ($5) a day and her 10-year-old son Mohammad helps her when he is not at school. (Photo by Ibraheem Abu Mustafa/Reuters)

A coach wipes away tears and comforts a girl who was feeling tired during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, May 4, 2016. (Photo by Aly Song/Reuters)