In this December 18, 2013 photo released by Six Flags Discovery Kingdom, 32 men dressed as Santa Claus ride the 150-foot tall SkyScreamer tower swing ride at Six Flags Discovery Kingdom in Vallejo, Calif. (Photo by Jason Quintos/AP Photo/Six Flags Discovery Kingdom)

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)

Tank crew standing in front of M-4 tank, Ft. Knox, Kentucky, June, 1942. (Alfred Palmer/OWI/LOC)

The new MacBook Pro is shown during the keynote address at the Apple 2012 World Wide Developers Conference (WWDC) at Moscone West on June 11, 2012 in San Francisco, California. This is Apple’s latest flagship laptop featuring an updated processor and a super high resolution screen that features 5.1 million pixels – 3 million more than a typical high-definition television.

A man smokes marijuana during a demonstration in support of the legalization of marijuana in Medellin, May 2, 2015. (Photo by Fredy Builes/Reuters)

Wounded Reuters photographer Gleb Garanich, who was injured by riot police, takes pictures as riot police block protesters during a scuffle at a demonstration in support of EU integration at Independence Square in Kiev November 30, 2013. Riot police in the Ukrainian capital Kiev used batons and stun grenades to disperse hundreds of pro-Europe protesters from the city's main Independence Square early on Saturday, witnesses said. (Photo by Reuters/Stringer)

A seven week old Daschund cross puppy waits to be re-homed at the Cheshire Dogs Home on January 4, 2010 in Warrington, England. (Photo by Christopher Furlong/Getty Images)

The Spirit of Ecstasy, also called “Emily”, “Silver Lady” or “Flying Lady,” was designed by English sculptor Charles Robinson Sykes and carries with her a story about a secret passion between John Walter Edward Douglas-Scott-Montagu (second Lord Montagu of Beaulieu after 1905, a pioneer of the automobile movement, and editor of The Car Illustrated magazine) and his love and the model for the emblem, his secretary Eleanor Velasco Thornton. Photo: Worker Ronald Little displays a finished “Spirit of Ecstasy”. (Photo by Stefan Wermuth/Reuters)