Two attendees compete in the biggest vape cloud competition at the Vape Summit 3 in Las Vegas, Nevada May 2, 2015. According to new research provided to Reuters, youngsters say that performing tricks is one of the top two reasons they began using e-cigs. (Photo by David Becker/Reuters)

“Mr Big Dipper”, Nicholas Roemmelt (Denmark). A stargazer observes the constellation of the Big Dipper perfectly aligned with the window of the entrance to a large glacier cave in Engadin, Switzerland. This is a panorama of two pictures, and each is a stack of another two pictures: one for the stars and another one for the foreground, but with no composing or time blending. (Photo by Nicholas Roemmelt/National Maritime Museum/The Guardian)

Ban Gioc – Detian Falls are two waterfalls on the Quây Sơn River, in Chinese Guichun River, straddling the Sino-Vietnamese border, located in the Karst hills of Daxin County, Guangxi (Chinese side), and in Trùng Khánh District, Cao Bằng province on the Vietnamese side, 272 km (169 mi) north of Hanoi. In Vietnamese, the two falls are considered as two parts of one waterfall with the sole name Bản Giốc. The two parts are called as: thác chính (Main waterfall) and thác phụ (Subordinate waterfall). Chinese texts sometimes name both falls from the Détiān falls on the Chinese side. During the summer rains the two waterfalls may join together.

A sheep, painted in the colours of World Cup participating country England looks on on September 11, 2011 in Dunedin, New Zealand. (Photo by David Rogers/Getty Images)

A policewoman uses her mobile phone as navy honor guards stand near of a World War Two memorial during celebrations to mark Victory Day in the Black Sea port of Odessa May 9, 2014. Ukraine celebrates the 1945 victory over Nazi Germany during World War Two on May 9. (Photo by Gleb Garanich/Reuters)

One of the two one-year-old albino alligator is seen in a vivarium at the Tropical aquarium in Paris. The two alligators are the result of a captive breeding program which protect endangered species and will presented to the public in a vivarium. (Photo by Philippe Wojazer/Reuters)

In this Wednesday, April 15, 2020 file photo, a motorcycle delivery man rides past a billboard urging people to stay home over the coronavirus pandemic in Dubai, United Arab Emirates. Wealthier Western countries are considering how to ease lockdown restrictions and start taking gradual steps toward reviving business and daily life. But many developing countries, particularly in the Middle East and Africa, can hardly afford the luxury of any misstep. (Photo by Jon Gambrell/AP Photo/File)