A woman loyal to the Houthi movement holds a rifle as she takes part in a parade to show support to the movement in Sanaa, Yemen September 6, 2016. The Saudi-led Arab coalition launched a military campaign against the Huthis and their allies in March 2015, after the rebels closed in on Gulf-backed President Abedrabbo Mansour Hadi in his southern refuge of Aden, forcing him into exile. (Photo by Khaled Abdullah/Reuters)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

Jeff Friesen's photography project entitled 'The Canadian: Ghost Train Crossing Canada' appears to show a train crossing Canada - but, in fact, the train is just two inches tall. His work captures the travels of a scale model vintage 1955 streamliner passenger train against picturesque landscapes.

In this August 31, 2017, photo, mock fish are displayed to offer to the ancestors during the “Hungry Ghost Festival” in Hong Kong. Countless hungry and restless ghosts are roaming Hong Kong, and the world, to visit their living ancestors, at least according to Chinese convention. In traditional Chinese belief, the seventh month of the lunar year is reserved for the Hungry Ghost festival, or Yu Lan, a raucous celebration marked by feasts and music. (Photo by Kin Cheung/AP Photo)

The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine, which was under the direct jurisdiction of the central authorities of the Soviet Union. The Chernobyl disaster is the worst nuclear power plant accident in history in terms of cost and resulting deaths, and is one of only two classified as a level 7 event (the maximum classification) on the International Nuclear Event Scale (the other being the Fukushima Daiichi nuclear disaster in 2011). Photo: Graffiti of a crying baby on a wall, Chernobyl Power Plant, Chernobyl, Ukraine. (Photo by Hans Neleman/Getty Images)

Army paratroopers carry the casket of Private Howard at the Wellington Cathedral on December 21, 2010 in Wellington, New Zealand. Private Howard was serving with the British army when was killed by friendly fire from a US Air Force plane in Helmand Province, Afghanistan earlier this month. Private Howard is the fifth NZ-born soldier to be killed in action in Afghanistan. (Photo by Marty Melville/Getty Images)

In this photo distributed by the Israeli Defense Forces (IDF) May 23, 2005, woman soldiers wear branches in their helmets as their infantry instructors' course learns about camouflage during the field craft week of their training May 19, 2005 at an army base near Beersheva in Israel's southern desert. It takes the IDF more than 2 months to teach these 18-year-old female recruits the basic arts of warfare before they assigned to pass on their newly-acquired skills to the army's male and female draftees. (Photo by Abir Sultan/IDF via Getty Images)