Newly commissioned 2nd lieutenants throw their caps in the air as a team of F-16 Air Force Thunderbirds fly over the 2011 graduating class of the U.S. Air Force Academy on May 25, 2011 in Colorado Springs, Colorado. A total of 1,021 graduates received their diplomas in front of their families and dignitaries at the Academy's Falcon Stadium. (Photo by John Moore/Getty Images)

A man stands next to his giant pumpkins as he waits for them to be weighed in at the 34th Annual Safeway World Championship Pumpkin Weigh-Off October 8, 2007 in Half Moon Bay, California. (Photo by Justin Sullivan/Getty Images)

Pernille Ferdinandsen receives a neck tattoo from Peter Madsen during the third Copenhagen Ink Festival which opened Thursday May 9, 2013 in Copenhagen, Denmark, the biggest tattoo festival in Northern Europe. During the three days, 180 of the world's best and most celebrated national and international tattoo artists show the audience their skills in making art on the body and tattoo's on the audience. (Photo by Lars Krabbe/AP Photo)

Competitors line up their boats for some formalities during the Aberdeen Dragon Boat Races. (Photo by Jessica Hromas)

Members of security forces secure Tahrir Square in Cairo, Egypt, November 11, 2016. Egypt imposed a big security clampdown in its cities on Friday as mass demonstrations called to protest against austerity measures failed to take place. Riot police and armored vehicles filled the otherwise empty streets of central Cairo, but most people stayed at home. (Photo by Mohamed Abd El Ghany/Reuters)

A dog in a purple dress, taken in El Dorado, Arkansas, December 2016. The dapper dogs in clothes are back with a second series, and they’re feeling festive. (Photo by Tammy Swarek/Barcroft Images)

Afghan men work in a small sweets factory in Kabul, Afghanistan January 5, 2017. (Photo by Mohammad Ismail/Reuters)

Impressive images of these alien-like creatures were captured underwater – photographer Cai Songda is a keen diver and did not miss the chance to snap pictures of the unique “aliens”. Here: A Tremoctopus Gracilis in the waters around Anilao, Philippines. (Photo by Cai Songda/Caters News Agency)