U.S. singer Katy Perry slips on the icing of a giant cake that she had jumped onto as part of her performance at the MTV Latin America Awards in Guadalajara, in this October 16, 2008 file photo. (Photo by Daniel Aguilar/Reuters)

Saudi youths demonstrate a stunt known as “sidewall skiing” (driving on two wheels) in the northern city of Tabuk, in Saudi Arabia December 3, 2014. (Photo by Mohamed Al Hwaity/Reuters)

This 1999 photo, supplied by HBO, shows a younger-looking James Gandolfini, who plays mob boss Tony Soprano, in an episode from the first season of the HBO cable television mob series, “The Sopranos”. Actor James Gandolfini, best known for his Emmy-winning portrayal of a conflicted New Jersey mob boss in the acclaimed HBO cable television series “The Sopranos”, has died while vacationing in Rome, the network said on June 19, 2013. (Photo by Anthony Neste/AP Photo/HBO)

South Korean students pose for a selfie following a traditional coming-of-age ceremony at Namsan hanok village in Seoul on May 15, 2017. The Coming of Age Day is the day to celebrate and encourage the youth who have reached the age of 20, which is considered the beginning of adulthood. (Photo by Ed Jones/AFP Photo)

In this Wednesday, July 23, 2014 file photo, Omaha photographer Lane Hickenbottom photographs the night sky in a pasture near Callaway, Neb. With no moon in the sky, the Milky Way was visible to the naked eye. More than one-third of the world’s population can no longer see the Milky Way because of man-made lights, according to a scientific paper by Light Pollution Science and Technology Institute's Fabio Falchi and his team members, published on Friday, June 10, 2016. (Photo by Travis Heying/The Wichita Eagle via AP Photo)

Guests on the terrace of Shepheard's Hotel, Cairo, circa 1940. (Photo by Hulton Archive/Getty Images)

An instructor (C) adjusts the posture of students of flight attendant major during a training session at Anhui Foreign Languages University, in Hefei, Anhui province, China, May 25, 2015. (Photo by Reuters/China Daily)

Princess Diana relaxes on the sand during a visit to the beach on the Caribbean Island of Nevis January 4, 1993. (Photo by Mark Cardwell/Reuters)