Costume actors to wait before the show at “Chian Tourism Day” Inauguration Ceremony in Ninghai Zhejiang Province on May 19, 2011 in Ninghai, China. Various activities in local famous historic sites are being held to mark the day “China Tourism Day” on May 19. (Photo by Lintao Zhang/Getty Images)

A rainbow appears over the Louisiana gulf May 26, 2010 in the Gulf of Mexico near Brush Island, Louisiana. (Photo by Win McNamee/Getty Images)

British prime minister Winston Churchill (1874–1965) stops to pet a cat at Liverpool Street Station, 24th May 1952. (Photo by Keystone/Hulton Archive/Getty Images)

A resident brings his dog that uses a mask in Jakarta, Indonesia, on May 12, 2020. (Photo by Jefta Images/Barcroft Media via Getty Images)

Icelandic horses play on a stud farm in Wehrheim Frankfurt, Germany, as the sun rises on Thursday, May 21, 2020. (Photo by Michael Probst/AP Photo)

Elephants dust themselves with soil at Taigan safari park in Belogorsk, Crimea on May 4, 2021. (Photo by Alexey Pavlishak/Reuters)

People wearing mushroom hats stand in front of the Washington Monument in Washington, D.C., U.S., May 14, 2021. (Photo by Andrew Kelly/Reuters)

A cow is seen on land that used to be under water, at the Aculeo Lagoon in Paine, Chile, May 14, 2018. (Photo by Matias Delacroix/Reuters)