In this March 22, 1975 file photo, a refugee clutches a baby as a government helicopter gunship carries them away near Tuy Hoa, Vietnam, 235 miles northeast of Saigon. They were among thousands fleeing from Communist advances. AP Photographer Nick Ut will be retiring from the AP in March 2017 after 51 years of taking photographs from the front lines of the Vietnam War to the red carpets of Hollywood. (Photo by Nick Ut/AP Photo)

A severe thunderstorm hits Omaha, Neb., on Wednesday, June 12, 2024. (Photo by Chris Machian/Omaha World-Herald via AP Photo)

A woman gets ready for her performance at the backstage of the Heart restaurant in Ibiza on June 29, 2015. Take the Spanish chefs Ferran and Albert Adria, the Cirque du Soleil founder French Guy Laliberte and contemporary artists such as Japanese Takashi Murakami. Put them together on the luxurious Mediterranean island of Ibiza and shake well to get “Heart” an innovative multi-sensory experience. The idea of provoking emotions through a collision of avant-garde creativities appeared two years ago from Adria brothers and Laliberte's passion about art and cuisine. They met a decade ago at the famous restaurant El Bulli, closed in 2011. (Photo by Jaime Reina/AFP Photo)

French artist Gino rides the “Celestial Cyclo” tricycle built by him in Le Marais neighbourhood in Paris, France, August 15, 2015. (Photo by Pascal Rossignol/Reuters)

2000 attended a welcome party at TigerTiger Manchester which was the first event in set of big club night for new students to Manchester and Salford universities in Manchester, UK on September 19, 2016. This year, university bosses have stepped up security in Manchester. (Photo by Jordan Sinclair/UK News Pictures)

People cheer as the ball drops at midnight in Times Square on January 1, 2015 in New York City. An estimated one million people from around the world are expected to pack Times Square to ring in 2015. (Photo by Andrew Theodorakis/Getty Images)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)

A woman crowd-surfs in front of the main stage at the Woodstock Festival in Kostrzyn-upon-Odra, close to the Polish-German border, August 2, 2014. Some 500 thousand people attended the festival that is the brainchild of Polish journalist and social campaigner Jerzy Owsiak. He initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Thomas Peter/Reuters)