Children hold signs thanking truck drivers hauling rocks to the Lake Oroville Dam after an evacuation was ordered for communities downstream from the dam in Oroville, California, U.S. February 13, 2017. (Photo by Jim Urquhart/Reuters)

The possible surface of TRAPPIST-1f, one of seven newly discovered planets in the TRAPPIST-1 system that scientists using the Spitzer Space Telescope and ground based telescopes have discovered. (Photo by Reuters/NASA/JPL-Caltech)

A man cries as he carries his daughter while walking from an Islamic State-controlled part of Mosul towards Iraqi special forces soldiers during a battle in Mosul, Iraq March 4, 2017. Reuters Photographer Goran Tomasevic: “Both screaming in terror, a father and the young daughter he cradled in his arm fled through the rubble-strewn streets of Wadi Hajar, transformed in a flash into a battleground between Islamic State fighters and Iraqi special forces. They and their neighbours – some wearing rubber sandals, some barefoot – were running from an IS counter-attack in this part of Mosul, dodging gunfire as the militants closed in”. (Photo by Goran Tomasevic/Reuters)

An Orthodox child is given an icy dip in a lake in celebration of Epiphan, near the village of Vorontsovka, some 20 km from the Kyrgyz capital of Bishkek, Kyrgyzstan, 19 January 2019. People believe that bathing in blessed waters during the holiday of Epiphany strengthens their spirit and body. (Photo by Igor Kovalenko/EPA/EFE)

Mil Mi-8 combat helicopter flies over Moscow, Russia on May 7, 2019 during the dress rehearsal of a Victory Day air show marking the 74th anniversary of the victory over Nazi Germany in the 1941-1945 Great Patriotic War, the Eastern Front of World War II. (Photo by Sergei Savostyanov/TASS)

Racegoers during Ladies Day at the Grand National Festival at Aintree Racecourse on April 13, 2018 in Liverpool, England. (Photo by Mercury Press)

An Afghan hunter shoots at a duck in Laghman province, Afghanistan on May 30, 2018. (Photo by Reuters/Parwiz)

Model Daisy Lowe has been camouflaged into a wall of daisies by world-leading body paint artist Carolyn Roper, to showcase the Samsung QLED TV's Ambient Mode feature in London, United Kingdom on August 2, 2018. The work took eight hours to complete. (Photo by Matt Alexander/PA Wire)