A tourist stands at an edge of the singing sand, the 150-metre-high by three-kilometre-long dune that generates a low-pitched, organ-like rumble in dry weather, in Altyn-Emel national park in Almaty region, Kazakhstan, May 12, 2016. (Photo by Shamil Zhumatov/Reuters)

A young migrant cries as she waits to cross the Greek-Macedonian border, near the village of Idomeni, Greece March 3, 2016. Thousands of refugees and migrants wait on the border between Greece and Macedonia and about 30,000 refugees and other migrants are stranded in Greece, with 10,000 at the Idomeni border crossing to Macedonia. (Photo by Marko Djurica/Reuters)

Museum employee Victoria views a giant grouper fish specimen at the Natural History Museum in west London March 25, 2015. It forms part of a new exhibition, “Coral Reefs: Secret Cities of the Sea”, featuring a panoramic virtual dive and over 250 specimens from the Museum's coral, fish and marine invertebrate collection, which opens on March 27. (Photo by Toby Melville/Reuters)

A man photographs the main engines of the space shuttle orbiter Discovery on display at the Udvar-Hazy Smithsonian National Air and Space Annex Museum in Chantilly, Virginia August 28, 2015. Shuttle Discovery had 27 years of service and flew 39 times before being retired in 2011. (Photo by Gary Cameron/Reuters)

NYC morning fog. Wednsday, January 15, 2014, morning dense fog creates spectacular views over the East river of lower Manhattan, Brooklyn and Manhattan bridges as New Yorkers and tourist admire the scenery. View from Brooklyn Bridge Park in DUMBO Brooklyn. (Photo by Paul Martinka/New York Post)

The Royal casket of King George Tupou V is carried towards the Royal Tombs during the State Funeral held for King George Tupou V at Mala'ekula on March 27, 2012 in Nuku'alofa, Tonga. King George died in Hong Kong on March 18th after six years as the King. (Photo by Sandra Mu/Getty Images)

People view artist David Byrne's installation "Tight Spot" beneath Manhattan's High Line park on September 27, 2011 in New York City. The 48-foot by 20-foot inflatable globe is squeezed beneath the steel support framework of the High Line and is accompanied with a rumbling audio soundtrack created by distorting Byrne's voice. (Photo by Mario Tama/Getty Images)

The first tram is delivered to the Gogar tram depot on October 17, 2011 in Edinburgh, Scotland. The tram was delivered on a low loader which had driven from Irun, northern Spain and is the first of 27 trams expected to arrive at the depot over the coming months. Last month the Scottish Government intervened to oversee the troubled Edinburgh trams project assigning project managers from Transport Scotland to work with contractors Bilfinger Berger. (Photo by Jeff J Mitchell/Getty Images)