A stunt rider jumps over spectators after the final stage of the annual ABSA Cape Epic mountain bike stage race, Cape Town, South Africa, 30 March 2014. The multi day stage race is know as the “Tour de France” of mountain biking and sees 1,200 riders riding 720km in seven days. The race includes the worlds leading professional racers along with amateur cyclists. (Photo by Kim Ludbrook/EPA)

A rainbow is seen near a cloud south of Corvallis, Ore., Monday, May 19, 2014. (Photo by Andy Cripe/AP Photo/The Corvallis Gazette-Times)

The antennas of the European Southern Observatory's Atacama Large Millimeter/Submillimeter Array, also known as ALMA, are set against the splendor of the Milky Way in this picture by Babak Tafreshi. Construction of the full ALMA array is due to be completed in Chile's Atacama Desert in 2013, but the facility is already making scientific observations with a partial array of antennas. (Photo by ESO/B. Tafreshi/TWAN)

Old Heidelberg, Dog with Pipe, 1905. (Photo by Detroit Publishing Company)

A hungry cow smiles for the camera in Salzburg, Austria. One of a series of funny animal mugshots taken by Chanel Cartell and Stevo Dirnberger during their travels around the globe. (Photo by Chanel Cartell/Stevo Dirnberger/Rex Features/Shutterstock)

Cloud inversion taken at Sunrise in Mam Tor, Derbyshire, UK on August 30, 2016. (Photo by David Zdanowicz/REX Shutterstock)

A girl sits on railway tracks at a makeshift camp for refugees and migrants at the Greek-Macedonian border near the village of Idomeni, Greece, March 19, 2016. (Photo by Alkis Konstantinidis/Reuters)

American film director Mike Todd and his actress wife Elizabeth Taylor get into a spat after missing their flight from London to Nice on June 22, 1957. (Photo by AP Photo)