“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)

Looters scramble in Philipsburg, St. Maarten, Sunday September 10, 1995 for goods in the Ram's department store, which contained mostly food and liquor. No attempts are currently being made by Dutch troops on the island to stop the looting, since few relief supplies have arrived in St. Maarten, which was ravaged on Tuesday by Hurricane Luis. (Photo by John McConnico/AP Photo)

“Lobsang and 66 fellow monks were imprisoned in 1959. When released 21 years later, he was one of only three survivors. While in prison his best friend, a rinpoche, died in his arms. Tensin was later discovered to be the reincarnation of that friend. Lobsang said there are so many characteristics of his old friend in the young boy”. (Photo and caption by Phil Borges)

Breath at sunset, captures a sea turtle at a dive site called Black Rock. Kāʻanapali, Hawaiʻi, August 2013. (Photo by Christopher Doherty/Smithsonian.com)

France's Christian Lavieille and co-pilot Jean-Michel Polato compete with their Proto Dessoude during the first stage of the Dakar Rally 2013 from Lima to Pisco January 5, 2013. (Photo by Jacky Naegelen/Reuters)

Members of the staff wait for the start of the maiden press conference for China's all-girl “boyband” FFC-Acrush in Beijing, China April 28, 2017. Picture taken April, 28, 2017. (Photo by Damir Sagolj/Reuters)

A Raramuris indigenous woman takes part in the “Ultra maraton de los Canones 2017” (Ultra marathon of the Canyons), at La Sinforosa Canyon, in Guachochi, Chihuahua state, Mexico on July 15, 2017. More than 600 participants from different countries take part in the 63 and 100 kilometers races, along the Tarahumara mountain range. (Photo by Herika Martinez/AFP Photo)

Expedition 44 flight engineer and NASA astronaut Scott Kelly seen inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the International Space Station. Kelly is one of two crew members spending an entire year in space. (Photo by Scott Kelly/NASA)