Men cover their heads from the sun while riding on a motorcycle during a hot day in Cairo, Egypt, August 17, 2015. A heatwave killed at least 61 people across Egypt from Sunday to Tuesday and caused nearly 600 people to be admitted to hospital, Egypt's health ministry said on state news agency MENA on Wednesday. (Photo by Amr Abdallah Dalsh/Reuters)

Workers transport a model of a dinosaur at the exhibition “World of Dinosaurs” at a former lignite surface mining area in Grosspoesna near Leipzig, central Germany, Wednesday, October 29, 2014. A 100-foot long statue of a dinosaur had to be moved Wednesday because German authorities had deemed it a safety risk. Officials feared the sculpture could cause traffic accidents by distracting drivers on a nearby highway. The reptile, one of 50 species on show in the World of Dinosaurs exhibit near Leipzig, was moved to a less conspicuous position further from the road. (Photo by Jens Meyer/AP Photo)

Workmen use a crane to winch a large stone head, created by British sculptor Emily Young, into Berkeley Square on February 2, 2012 in London, England. (Photo by Oli Scarff/Getty Images)

A visitor stands in front of a portrait taken by artist Bruce Gilden at the “Masters of Photography” exhibition at the Photokina trade fair in Cologne on September 20, 2016. The fair for the photographic and imaging sector, that is running from September 20 to 25, 2016, presents products from image capture, image processing and storage to image output. Photokina also includes a program of events with congresses, workshops, symposiums and photography exhibitions. (Photo by Patrik Stollarz/AFP Photo)

Aerial view of a boat working in the green water of Taihu Lake covered by blue-green algae, Wuxi city, Jiangsu province, China on May 23, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)

A suspected Vietcong is kicked by a Vietnamese soldier holding a rifle as another soldier attempts to tie his hands on October 22, 1965. The prisoner was one of 15 captured October 21 near Xom Chua when government troops raided in the plain of reeds area. Troops killed 43 suspected Vietcong and seized some arms. (Photo by Richard Merron/AP Photo)

A so-called “Supermoon” dominates the sky while traffic rolls in the streets in Naypyitaw, Myanmar, 03 December 2017. According to the National Aeronautics and Space Administration (NASA) a series of three “Supermoons” – dubbed the “Supermoon trilogy” – will appear in the sky on 03 December 2017, on 01 January 2018 and and 31 January 2018. A “Supermoon” commonly is a full moon at its closest distance to the earth with the moon appearing larger than usual. (Photo by Hein Htet/EPA/EFE)

An aircraft passes over houses at it lands at Heathrow Airport near London, Britain, December 11, 2015. Picture taken December 11, 2015. (Photo by Neil Hall/Reuters)