A man takes a picture of sea spray as storms hit Cape Town, South Africa, June 7, 2017. (Photo by Mike Hutchings/Reuters)

A man takes a picture of models as they pose next to Cosmis Racing Wheels products during the 2016 Moscow International Auto Salon in Moscow, Russia, August 26, 2016. (Photo by Sergei Karpukhin/Reuters)

President Barack Obama with does the tango with a dancer during the State Dinner at the Centro Cultural Kirchner, Wednesday, March 23, 2016, in Buenos Aires, Argentina. (Photo by Pablo Martinez Monsivais/AP Photo)

An actress dressed as Wonder Woman walks between visitors during the season inauguration of the Madrid Warner amusement park in San Martin de Valdeiglesias, near Madrid, Spain, March 18, 2016. (Photo by Andrea Comas/Reuters)

An Indonesian muslim woman walks on “sea of sands” as they prepare for Eid Al-Fitr prayer at Parangkusumo beach on July 17, 2015 in Yogyakarta, Indonesia. Muslims worldwide observe the Eid Al-Fitr prayer to mark the end of Ramadan and the beginning of the new month of blessing Shawwal 1436 Hijriah. (Photo by Ulet Ifansasti/Getty Images)

Private Harold L. Langhofer edges into the ball-turret, March 9, 1943. Curled in this position, he can turn the turret so that it fires in any direction. The turret can also be swung around so that the hatch opens into the plane, and the gunner can crawl into it while the Flying Fortress is in motion. (Photo by AP Photo)

A partial Solar eclipse is seen just after sunrise over the Queens borough of New York across the East River on November 3, 2013 in New York. (Photo by Stan Honda/AFP Photo)

“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)