A child parades on a float during the Bun Festival on May 25, 2015 in Hong Kong, Hong Kong. One of Hong Kong's most colourful cultural celebration event, Cheung Chau Bun Festival, will be staged on 25 May 2015 (Monday) till 26 May 2015 midnight (Tuesday). This festival has over 100 years of history. Every year, thousands of people descend upon the tiny island for The Piu Sik (Floating Colours) Parade, Lucky Bun (Ping On Bun) and The Bun Scrambling Competition, the ancient custom during the festival. (Photo by Lam Yik Fei/Getty Images)

Afghan air force 2nd Lt. Niloofar Rhmani walks the flight line at Shindand Air Base, Afghanistan, prior to her graduation from undergraduate pilot training, on May 13, 2013. Rhmani made history on May 14, when she became the first female to successfully complete undergraduate pilot training and earn the status of pilot in more than 30 years. She will continue her service as she joins the Kabul Air Wing as a Cessna 208 pilot. (Photo by Senior Airman Scott Saldukas/USAF)

In this Thursday, May 16, 2013 file photo, Finland's Krista Siegfrids, second right, kisses a dancer as she performs her song “Marry Me” during the second semifinal of the Eurovision Song Contest at the Malmo Arena in Malmo, Sweden. That was the first girl-on-girl kiss in the history of the annual competition. Previously, organizers had sought to prevent similar embraces citing the competition's status as a family event. (Photo by Alastair Grant/AP Photo)

Monumental landscape artwork “Hush” by installation artist Steve Messam hangs in the moors of Teesdale on July 18, 2019 in Barnard Castle, England. The outdoor installation is inspired by the geology, mining history and landscape of the area. It hangs over Bales Hush, a deep gauge in the terrain created when miners flushed the area with water to reveal the geological riches below. Hundreds of metres of recyclable saffron yellow fabric blow in the wind. (Photo by Christopher Thomond/The Guardian)

The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in Ukraine, which was under the direct jurisdiction of the central authorities of the Soviet Union. The Chernobyl disaster is the worst nuclear power plant accident in history in terms of cost and resulting deaths, and is one of only two classified as a level 7 event (the maximum classification) on the International Nuclear Event Scale (the other being the Fukushima Daiichi nuclear disaster in 2011). Photo: Graffiti of a crying baby on a wall, Chernobyl Power Plant, Chernobyl, Ukraine. (Photo by Hans Neleman/Getty Images)

“In 1967, Zhang Yaxin was 34 and working as a photojournalist at China’s state-controlled Xinhua News Agency when he was assigned to a top-secret government project. He was to be the official photographer of a new arts program led by Chairman Mao and his wife – the Model Operas. Though he was not to know it then, Zhang would spend the next seven years documenting the evolution of one of the most dramatic and elaborate attempts to redefine artistic sensibilities in modern art history”. – Chengcheng Jiang via TIME. Photo: Raid on the White Tiger Regiment, 1971. (Photo by Zhang Yaxin/Courtesy See+ Gallery, Beijing)

Women wearing traditional hats, known as a non la, sell fruits in Hoi An, Vietnam April 4, 2016. The non la hats are made of readily available materials such as palm leaves, tree bark and bamboo and are visible everywhere in the city, a UNESCO World Heritage site. Hoi An's history as a busy trading port is evident throughout its architecture, a mix of eras and styles, with traditional wooden Vietnamese houses, Chinese temples and French colonial buildings. (Photo by Jorge Silva/Reuters)

Combine harvesters work on a wheat field of the Solgonskoye farming company near the village of Talniki, southwest from Siberian city of Krasnoyarsk, Russia, August 27, 2015. Russia, one of the world's top wheat exporters, will harvest its third-largest grain crop in post-Soviet history this year, leading Russian consultancy SovEcon said on August 27 after upgrading its forecast. (Photo by Ilya Naymushin/Reuters)