The Doppler on Wheels (DOW) vehicle scans a supercell thunderstorm during a tornado research mission, May 8, 2017 in Elbert County near Agate, Colorado. Doppler on Wheels (DOW) is a mobile doppler radar mounted on a truck that brings instruments directly into storms, allowing scientists to scan storms and tornadoes and make 3-D maps of wind and debris. (Photo by Drew Angerer/Getty Images)

German troops in Stalingrad, USSR. September 10, 1942. (Photo by TASS)

A horse is ridden out of the River Eden after being washed on the first day of the Appleby Horse Fair on June 7, 2018 in Appleby, England. The fair is an annual gathering for Gypsy, Romany and travelling communities. The event has existed under the protection of a charter granted by James II since 1685 and it remains one of the key meeting points for these communities. Around 10,000 travellers are expected to attend the event who traditionally come to buy and sell horses and it offers an opportunity for the traveller community to come together to celebrate their heritage and culture. (Photo by Ian Forsyth/Getty Images)

An Afghan hunter shoots at a duck in Laghman province, Afghanistan on May 30, 2018. (Photo by Reuters/Parwiz)

Darth Vader balloon above Clifton Suspension Bridge during the hot air balloons mass ascent at sunrise on the first day of the Bristol International Balloon Fiesta on August 8, 2019 in Bristol, England. The Bristol International Balloon Fiesta is Europe's largest annual meeting of hot air balloons, attracting over 130 hot air balloons from across the globe. (Photo by Finnbarr Webster/Getty Images)

Participants from a North Korea military band perform during the Spasskaya Tower international military music festival in Red Square in Moscow, Russia, Friday, August 23, 2019. (Photo by Alexander Zemlianichenko/AP Photo)

A picture made available 26 April 2016 shows a tiger playing in the water with a trainer nicknamed “Super Tiger Man” at the Tiger Temple in Kanchanaburi province, Thailand, 24 April 2016. The site known in Thai as “Wat Pa Luangta Maha Bua Yannasampanno” has been the focus of a dispute with the Department of National Parks, Wildlife and Plant Conservation (DNP) after the DNP asked in 2015 that the temple hands over its 147 tigers since it was not licensed to keep them. The temple has requested for a zoo license according to its managing director. (Photo by Diego Azubel/EPA)

Groundhog Club co-handler Al Dereume holds Punxsutawney Phil, the weather prognosticating groundhog, in front of the crowd gathered for the 133rd celebration of Groundhog Day on Gobbler's Knob in Punxsutawney, Pa. Saturday, February 2, 2019. Phil's handlers said that the groundhog has forecast an early spring. (Photo by Gene J. Puskar/AP Photo)