Photographers gather to take pictures of pilot Andre Borschberg (C) ahead of the take off of Solar Impulse 2-a solar powered plane- in Nanjing, China, May 31, 2015. The world's largest solar-powered airplane, Solar Impulse 2, took off from eastern China's Nanjing on Sunday to continue its round-the-world voyage. The Swiss-made plane left Nanjing's Lukou International Airport at 2:39 in the early morning, with former fighter pilot Borschberg at the controls alone for the entire 8,200-kilometer flight from Nanjing to Hawaii, the toughest leg of its marathon adventure. (Photo by Reuters/Solar Impulse)

A Muslim woman takes a picture of a man in the water of the Mediterranean sea in Tel Aviv during Eid al-Fitr, which marks the end of the holy month of Ramadan July 19, 2015. Thousands of Palestinians used permits given by the Israeli authorities allowing many to enjoy the beaches along Israel's Mediterranean shoreline during the Eid al-Fitr holiday. (Photo by Baz Ratner/Reuters)

Women wearing sunglasses pose for a group photo at a park in Beijing in 1980. (Photo by Reuters/China Daily)

Rescue workers stand near dead bodies washed ashore in Ton Sai Bay in Thailand's Phi Phi island in this December 28, 2004 file photo. On December 26, 2004, a magnitude 9.15 quake off the coast of Indonesia's Aceh province triggered an Indian Ocean tsunami that killed around 226,000 people in Indonesia, Sri Lanka, India, Thailand and nine other countries. (Photo by Luis Enrique Ascui/Reuters)

A fellow officer comes to the aid of injured patrolman C.V. Satt, who was pelted with rocks and beer bottles during a clash between police and relief demonstrators in Denver September 23, 1935. (Photo by Henry G. Eisenhand/AP Photo)

A Palestinian protester sets fire to himself as he throws a molotov cocktail during clashes with the members of the Israeli armed forces in the West Bank city of Hebron, 13 October 2015. The past 12 days have seen the worst spell of street violence in Israel and the Palestinian areas in years, stirred in part by Muslim anger over perceived changes to the status quo observed at a disputed Jerusalem holy site. Sixteen Palestinians from the West Bank and Jerusalem have been killed, but more than half of them have been attackers shot dead after or during attempts to stab Israelis. (Photo by Abed Al Hashlamoun/EPA)

Sunday night, Lauren Watts searches for her dog in Mayflower, Arkansas., after a tornado struck the town. (Photo by Benjamin Krain/The Arkansas Democrat-Gazette)

“Kilauea Rules”. The most extreme place we put ours kayakers to paddle till now. Photo location: Big Island, Hawaii. (Photo and caption by Alexandre Socci/National Geographic Photo Contest)