Londoners sleep on the platform and on the train tracks at Aldwych Underground station,London, during heavy all night Nazi bombing raids, October 8, 1940. (Photo by AP Photo)

Visitors wear shirts with an image of former Chinese leader Mao Zedong at the Shanghai World Expo site in Shanghai, May 2, 2010. (Photo by Aly Song/Reuters)

A woman spits red paint as if it is blood protesting against bullfights in Madrid, Spain on March 27, 2016. Anti-bullfighting protesters have turn the iconic square of “Puerta del Sol” into a bullring. Protesters, almost naked covered with red paint as if it was blood, have demanded the abolition of bullfights under the slogan “The bull suffers!”. (Photo by Marcos del Mazo/Pacific Press)

The 30th anniversary of the meltdown at the Chernobyl nuclear plant that caused large amounts of radioactive particles to be released into the air will be commemorated on April 26, 2016. Photojournalist Sean Gallup returned to the area to document the lasting effects of the world's worst nuclear power plant accident. Pictured, children's beds are seen in an abandoned kindergarten in Kopachi village located inside the Chernobyl exclusion zone, September 29, 2015, near Chernobyl, Ukraine. (Photo by Sean Gallup/Getty Images)

Visitors take photos of a child dressed in a traditional costume before a folk performance in Panyu, Guangdong province, China on April 20, 2018. (Photo by Reuters/China Daily)

American singer/songwriter Ashley Nicolette Frangipane, known professionally as Halsey arrives at Playboy's Midsummer Night's Dream at the Marquee Nightclub at The Cosmopolitan of Las Vegas on July 29, 2018 in Las Vegas, Nevada. (Photo by Gabe Ginsberg/Getty Images)

This undated photo provided by NOAA in May 2018 shows aurora australis near the South Pole Atmospheric Research Observatory in Antarctica. When a hole in the ozone formed over Antarctica, countries around the world in 1987 agreed to phase out several types of ozone-depleting chemicals called chlorofluorocarbons (CFCs). Production was banned, emissions fell and the hole shriveled. But according to a study released on Wednesday, May 16, 2018, scientists say since 2013, there’s more of a banned CFC going into the atmosphere. (Photo by Patrick Cullis/NOAA via AP Photo)

In this October 7, 2018 photo waitress dance in the Hofbraeu tent after the closing of the Oktoberfest beer festival in Munich, southern Germany, which ran from September 22 through October 7, 2018. (Photo by Felix Hoerhager/AP Photo)