A staff member demonstrates how she puts on the helmet of a mock space suit at the C-Space Project Mars simulation base in the Gobi Desert outside Jinchang, Gansu Province, China, April 17, 2019. The facility – comprising several interconnected modules including a greenhouse and a mock decompression chamber – opened its doors to the public. (Photo by Thomas Peter/Reuters)

In this Tuesday, April 16, 2019, file photo, a visitor posing for a photo walks though azalea blossoms at Nezu Shrine during a day of mild spring weather in Tokyo. Nezu Shrine is one of the oldest shrines in Tokyo. (Photo by Eugene Hoshiko/AP Photo/File)

A girl cools off from the heat in water from an open fire hydrant in the Washington Heights section of upper Manhattan in New York City, New York, U.S., July 19, 2019. (Photo by Mike Segar/Reuters)

A youth rides his bicycle at Times Square, in New York City, U.S., August 14, 2019. (Photo by Lucas Landau/Reuters)

A toddler dressed as Hindu Lord Krishna takes part in Krishna Janmashtami celebrations at a temple in Kolkata, India, on August 23, 2019. Krishna Janmashtami is an annual Hindu festival that celebrates the birth of Lord Krishna, the eighth avatar of Vishnu. (Photo by Tumpa Mondal/Xinhua News Agency)

LiLou the therapy pig stands in front of a departures board at San Francisco International Airport in San Francisco, California, U.S. October 4, 2019. (Photo by Jane Ross/Reuters)

Bikini Contest in Daytona Beach, Florida’s Atlantic coast, circa 1980s. (Photo by Evan Hurd/Sygma/Sygma via Getty Images)

Blossoms and dust are blown by the wind as Jasmin Ricks, left, and her sister, Jessica Ricks, center, take in the cherry blossoms near the Tidal Basin in Washington on April 12, 2018. (Photo by Matt McClain/The Washington Post)