Lightning streaks across the sky as lava flows from a volcano in Eyjafjallajokul April 17, 2010. (Photo by Lucas Jackson/Reuters)

A boat commutes across the Mekong river in Phnom Penh on August 8, 2014. The Mekong is the world's twelth longest river running from the Tibetan Plateau through China's Yunnan province, Myanmar, Laos, Thailand, Cambodia and Vietnam. (Photo by Tang Chhin Sothy/AFP Photo)

Cheerleaders let their hair fly as they perform prior to a German first division Bundesliga soccer match between 1. FC Cologne and Bayern Munich in Cologne, Germany, March 4, 2017. (Photo by Michael Probst/AP Photo)

A group of colorful row houses are reflected on to the top of a black car parked on 3600 block of N street in the Georgetown section of Washington DC, February 16, 2017. (Photo by John McDonnell/The Washington Post)

A man dressed up as the devil jumps over babies lying on a mattress in the street during “El Colacho”, the “baby jumping festival” in the village of Castrillo de Murcia, near Burgos on June 18, 2017. Baby jumping (El Colacho) is a traditional Spanish practice dating back to 1620 that takes place annually to celebrate the Catholic feast of Corpus Christi. During the act – known as El Salto del Colacho (the devil's jump) or simply El Colacho – men dressed as the Devil jump over babies born in the last twelve months of the year who lie on mattresses in the street. (Photo by Cesar Manso/AFP Photo)

This undated handout photo received from the Antarctic Ocean Alliance on October 28, 2016 shows a adelie penguin jumping onto the ice in the Ross Sea in Antarctica. The world's largest marine reserve aimed at protecting the pristine wilderness of Antarctica will be created after a “momentous” agreement was finally reached on October 28, 2016 with Russia dropping its long-held opposition. (Photo by John Weller/AFP Photo/Antarctic Ocean Alliance)

Passengers hold 500 (bottom) rupee banknotes to buy train tickets at a railway booking counter in Allahabad, India, November 9, 2016. People are queuing up outside banks across India to exchange 500 and 1,000 rupee notes after they were withdrawn as part of anti-corruption measures. Indians will be able to exchange their old notes, which stopped being legal tender at midnight on Tuesday, for new ones at banks until 30 December. The surprise move is part of a government crackdown on corruption and illegal cash holdings. Banks were shut on Wednesday to allow them enough time to stock new notes. There are also limits on cash withdrawals from ATMs. The BBC's Yogita Limaye in Mumbai says there have been chaotic scenes outside many banks. (Photo by Danish Siddiqui/Reuters)

A coach wipes away tears and comforts a girl who was feeling tired during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, May 4, 2016. (Photo by Aly Song/Reuters)