The northern lights, or aurora borealis, illuminate the sky over Flakstad beach on Lofoten Islands in the Arctic Circle on September 5, 2017. (Photo by Jonathan Nackstrand/AFP Photo)

An Exmoor wild goat silhouetted in the sky over the Bristol Channel at the valley of the Rocks, North Devon, as the UK's heat wave continues on July 19, 2018. (Photo by Paul Silver/South West News Service)

Frost covers part of the face of University of Minnesota student Daniel Dylla during a morning jog along Mississippi River Parkway Tuesday, January 29, 2019, in Minneapolis. Extreme cold and record-breaking temperatures are crawling into parts of the Midwest after a powerful snowstorm pounded the region, and forecasters warn that the frigid weather could be life-threatening. (Photo by David Joles/Star Tribune via AP Photo)

Transgender actress Aubrey Banks presents a creation from the CHULO underwear collection ahead of CHULO founder and lead designer Ricardo Muniz during the New York Fashion Week, in a show that raised money for transgender and cisgender young women victims of violence, in New York, U.S. February 7, 2019. (Photo by Andrew Kelly/Reuters)

A humpead wrasse, transported from Japan's southern island of Okinawa, swims with other tropical saltwater fish on display in a tank for the Sony Aquarium 2017 exhibition in Tokyo on July 31, 2017. The Sony Aquarium 2017 exhibition, featuring marine life common to the waters around Okinawa, runs until August 13. (Photo by Kazuhiro Nogi/AFP Photo)

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)

Chieftain Japarupi Waiapi shows a roasted monkey -part of Waiapi's diet, also based in Manioc and fruits- at the reserve in Amapa state in Brazil on October 13, 2017. When Waiapis walks into the Amazon forest surrounding their village, they do not see trees, but a kind of shopping mall providing medicine, food, shelter, tools and weapons all under the eye of multiple spirits. (Photo by Apu Gomes/AFP Photo)

A colourful morning sunrise on Christmas Eve at Victoria Tower on Castle Hill, West Yorkshire, England on December 24, 2017. The history of human activity on the Castle Hill goes back over 4000 years. The site was developed as an iron age hill fort, surrounded by defensive ditches and ramparts. In the Middle Ages there was a castle on the hill, of which the well remains. The present tower was built to commemorate Queen Victoria's Diamond Jubilee of 1897. (Photo by Charlotte Graham/ZUMA Wire/Rex Features/Shutterstock)