A worker cleans the statue of Yuri Gagarin, the first person who flew to space, ahead of Cosmonautics Day celebrated on April 12, in Moscow, Russia, Wednesday April 10, 2019. Cosmonautics Day marks when Soviet cosmonaut Yuri Gagarin became the first man to fly in space, in 1961, orbiting the earth once before making a safe landing. (Photo by Maxim Marmur/AP Photo)

Sloth “Paula” hangs from a branch in her enclosure at the zoo in Halle an der Saale, eastern Germany, on June 14, 2019. The two-toed sloth celebrated her 50th birthday and is, according to the zoo, the oldest sloth of the world. (Photo by Hendrik Schmidt/dpa/AFP Photo)

Festival goers attend Splendour In The Grass 2019 on July 20, 2019 in Byron Bay, Australia. Splendour is an annual Australian music festival, showcases popular and established musical artists, as well as emerging Australian artists. (Photo by Mark Metcalfe/Getty Images)

A man sets himself on fire during protest rallies in front of the presidential office in Kiev, Ukraine on February 26, 2020. The man, who called himself Oleksandr Burlakov, said subsequently that his motive was to draw the attention of the authorities to his plight, related to the ownership of the land parcel. (Photo by Ihor Behus/Reuters)

N.C. Dezendorf, wife of the general manager of the Electro-Motive division of General Motors, christens the new lightweight “Aerotrain” at the company's locomotive works in La Grange, Ill. on August 22, 1955. (Photo by Edward Kitch/AP Photo)

Cao Ri and Xu Jiaqian have a wedding photograph taken in a pool at the Qianyishi Underwater Photography Studio in Beijing, China on September 7, 2017. (Photo by Thomas Peter/Reuters)

People dance in a park on a foggy day in Huai'an, Jiangsu province, China October 10, 2017. (Photo by Reuters/China Stringer Network)

Yippie leader Jerry Rubin, barred on December 4, from House Un-American Activities subcommittee hearing, aims a toy gun in “self defense” outside the Washington hearing room on December 5, 1969. Rubin showed up in his Santa Clause suit because he believed it was typical of the committee which, he said, “is a total circus”. (Photo by Bob Daugherty/AP Photo)