The main church in the town of San Damian Texoloc, Mexico stands in front of the Popocatepetl volcano as is spews ash and vapor early Tuesday, July 9, 2013. Last Saturday, Mexico's National Center for Disaster Prevention raised the volcano alert from Stage 2 Yellow to Stage 3 Yellow, the final step before a Red alert, when possible evacuations could be ordered after the Popocatepetl volcano spit out a cloud of ash and vapor 2 miles (3 kilometers) high over several days of eruptions. (Photo by J. Guadalupe Perez/AP Photo)

Katy Perry attends the European premiere of Katy Perry: «Part Of Me 3D» at Empire Leicester Square on July 3, 2012 in London, England. (Photo by Mike Marsland)

Clouds float over an open field January 3, 2007 in Shirley Heights, Antigua. (Photo by Joe Raedle/Getty Images)

LGBT activists take part in a “Rave Pride” demanding state support for the local LGBTQ outside Ukrainian President's office in Kyiv, Ukraine on July 30, 2021. (Photo by Gleb Garanich/Reuters)

A glass skywalk in Wanyuan, Sichuan province, built along the side of a cliff, is the highest such skywalk anywhere in China on January 31, 2017. Some visitors have been proven to be terrified by the experience had to brace against the wall in fear. (Photo by Chinanew.com/AsiaWire)

A view of a stampede is seen during a New Year's celebration on the Bund, a waterfront area in central Shanghai, December 31, 2014. The stampede killed at least 35 people and injured 43 during New Year's Eve celebrations in Shanghai, on the city's famed waterfront tourist strip known as the Bund, authorities said. (Photo by Reuters/Stringer)