An Army Sikorsky R-5 helicopter, undergoing record trials, demonstrates its lifting power by carrying 17 persons and pilot aloft as female onlookers wave in Bridgeport, Conn., January 10, 1946. During the tests records were claimed for altitude speed and both altitude and speed with payload. (Photo by Anthony Camerano/AP Photo)

In this Wednesday, April 12, 2017, photo, waitresses wait outside a restaurant in Pyongyang, North Korea. A generational divide is quietly growing in North Korea, often hidden behind relentless propaganda. On the streets there are young women in not-quite mini-skirts and teenage boys with baseball hats cocked sideways, K-pop style. (Photo by Wong Maye-E/AP Photo)

A Kenya Wildlife Services (KWS) veterinarian and security personnel back away from a tranquilised black-Rhino calf August 30, 2017 after she appeared to prematurely overcome the sedative at the Nairobi National Park, during an identification-tagging excercise to ease quick identification of resident rhino during anti-poaching patrols. (Photo by Tony Karumba/AFP Photo)

Mercury and Maia, fueled and overhauled, are waiting in the Tay at Dundee, for favorable weather to start the flight to the Cape, a distance of 6,370 miles. The composite machine moored in the Tay River, at Dundee, on September 23, 1938. (Photo by AP Photo)

Prepare yourself for some rib-tickling laughter because the Comedy Wildlife Awards has announced its finalists. Founded by Tanzania-based photographers Paul Joynson-Hicks MBE and Tom Sullam, the aim of the awards is to put a spotlight on wildlife conservation efforts while simultaneously injecting some humour into the world of wildlife photography. Here: Mountains Gorilla is making grimaces, as he came out of the bush after the rain, in Virunga National Park, Rwanda. (Photo by Josef Friedhuber/Comedy Wildlife Photography Awards/Barcroft Media)

Ethnic Miao women wearing traditional costumes take part in a parade during the traditional Lusheng (reed-pipe wind instrument) festival in Gulong, Guizhou province, China November 15, 2017. (Photo by Reuters/China Stringer Network)

A Buddhist monk lights a candle at Wat Phra Dhammakaya during a ceremony on Makha Bucha Day in Pathum Thani province, north of Bangkok February 22, 2016. Makha Bucha Day honours Buddha and his teachings, and falls on the full moon day of the third lunar month. (Photo by Jorge Silva/Reuters)

Expedition 44 flight engineer and NASA astronaut Scott Kelly seen inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the International Space Station. Kelly is one of two crew members spending an entire year in space. (Photo by Scott Kelly/NASA)