A smokejumper leaps from an airplane during a training flight above Winthrop, Washington, U.S., June 30, 2016. On a 100-degree day in early June, eight experienced firefighters did sit-ups in a semicircle training to parachute into a wildfire. Better known as “rookie candidates”, they were determined to make it through the five-week program at North Cascades Smokejumper Base in Winthrop, Washington, where the first experimental jumps occurred in 1939. (Photo by David Ryder/Reuters)

In this photo taken on Friday, July 14, 2017, a student at a paramilitary camp for children calls the rank to attention outside Kiev, Ukraine. As the deadly conflict in eastern Ukraine entered its third year, some parents in Ukraine are anxious to make sure their children are ready to fight it, instead of swimming and playing volleyball. (Photo by Efrem Lukatsky/AP Photo)

A picturesque supercell formation in the northwest of Booker, Texas from June 2013. (Photo by Mike Olbinski/Barcroft Media)

“Camille Lepage, a 26-year-old French photojournalist who had spent months documenting deadly conflict in Central African Republic has been killed, the French presidency said Tuesday, May 13. Lepage, a freelance photographer whose work was published in major French and American newspapers, died in western Central African Republic not far from the border with Cameroon, authorities said”. – Associated Press. Photo: Anti-balaka fighters from the town of Bossembele patrol in the Boeing district of Bangui, Central African Republic, February 24, 2014. (Photo by Camille Lepage/Reuters)

Visitors view ice sculptures at the 29th Harbin International Ice and Snow Festival on January 5, 2013. (Photo by Associated Press)

A Palestinian youth demonstrates his parkour skills on a street in Gaza City, January 15, 2016. (Photo by Suhaib Salem/Reuters)

Michael Bath, from McLeans Ridges in New South Wales, Australia, estimates that in his lifetime he has taken more than 3,500 images of lightning bolts illuminating the sky. Photo: Alstonville, New South Wales, Australia – January 8, 2003. (Photo by Michael Bath/Caters News)