A girl reacts as she receives polio vaccine drops during a house-to-house vaccination campaign in Yemen's capital Sanaa, November 10, 2015. (Photo by Khaled Abdullah/Reuters)

On the western side of Mount Hood lies the longest glacier cave system in the contiguous United States. In 2012, these caves were mapped to a combined length of 7,166.8 feet by cave explorers Brent McGregor and Eddy Cartaya. Currently, the total passage length is hundreds of feet less. Glaciers are frozen rivers; they are always moving and changing... (Photo and caption by Josh Hydeman)

This is the mesmerising image of a colourful Milky Way shining down on Mount Fuji. Steve Lance Lee, 37, captured the sky above the iconic mountain whilst on his honey moon in Lake Kawaguchiko, Japan. Mount Fuji is illuminated underneath the galaxy of stars, creating an impressive landscape. Here: The beautiful image captured by Steve Lance Lee of the Milky Way seemingly errupting from Mt. Fuji in Japan. (Photo by Steve Lance Lee/Caters News)

Sumo wrestlers perform a show fight during an annual sumo tournament dedicated to the Yasukuni Shrine in Tokyo, Japan on April 16, 2018. (Photo by Toru Hanai/Reuters)

A ballet dancer brushes on blush as she prepares for a street ballet performance in Mexico City, Saturday, July 28, 2018. In this sprawling megalopolis notorious for its clogged streets, a theater company sent out tutu-clad dancers out to delight motorists at snarled intersections with snippets from ballet classics like “The Nutcracker” and “Swan Lake” all in the 58 seconds it takes for the light to go from red to green. (Photo by Emilio Espejel/AP Photo)

Neon sea creatures have been captured lighting up the ocean with their vibrant colors – in what looked like a scene from Avatar. Photographer Simon Pierce, 39, took the images over several months after visiting both Nosy Sakatia in Madagascar and Mafia Island in Tanzania recently. (Photo by Simon Pierce/Caters News Agency)

A Syrian man sells vegetables in front of a damaged tank in Homs, on December 20, 2024. Islamist-led rebels took Damascus in a lightning offensive on December 8, ousting president Bashar al-Assad and ending five decades of Baath rule in Syria. (Photo by Sameer Al-Doumy/AFP Photo)

New autopilot features are demonstrated in a Tesla Model S during a Tesla event in Palo Alto, California, 2015. Federal officials say the driver of a Tesla S sports car using the vehicle’s “autopilot” automated driving system has been killed in a collision with a truck, the first U.S. self-driving car fatality. The National Highway Traffic Safety Administration said preliminary reports indicate the crash occurred when a tractor-trailer made a left turn in front of the Tesla at a highway intersection. Joshua D. Brown, of Canton, Ohio, died in the accident May 7 in Williston, Florida, when his car's cameras failed to distinguish the white side of a turning tractor-trailer from a brightly lit sky and didn't automatically activate its brakes, according to government records obtained Thursday. (Photo by Beck Diefenbach/Reuters)