BOSTON — China's Xiaoshan airport shut down for an hour on Wednesday. The reason: an unidentified flying object.
As the conspiracy theories circulate, here's a look back at some other UFO incidents — in art, popular culture and maybe even in real life.
A video-recorder grab taken by Taiwan resident Lee Chun-hung in northern Taiwan, Dec. 12, 1999, shows a ball of fire trailing across the sky. (AFP/Getty Images)
An image from video footage taken Nov. 14, 1999, by a Beijing resident shows an unidentified flying object hovering over Beijing city center late in the afternoon. (AFP/Getty Images)
The Devil's Marbles, a rock formation near Wycliffie Wellin Australia that UFO spotters believe has regularly been visited by extraterrestrials. (Chris McCall/AFP/Getty Images)
A warning sign marks the boundary of Area 51, March 12, 2000, in Rachel, Nevada. (Dan Callister/Getty Images)
William Protor polishes a model flying saucer on property near Jamul, California, Oct. 15, 2000, purchased by the Unarius Academy of Science to serve as a future landing site for "space brothers" from other planets. (David McNew/Newsmakers)
Visitors look at a model depicting the 1947 Alien Autopsy in Roswell, New Mexico, during the "The Science of Aliens" exhibition at the Miraikan, the National Museum of Emerging Science and Innovation in Tokyo on June 3, 2008. (Toshifumi Kitamura/AFP/Getty Images)
Visiters view the frame of a flying saucer made by Chinese peasant Du Wenda at his researching base January 7, 2005 in Xiao County, China. (China Photos/Getty Images)
Major Jesse Marcel from the Roswell Army Air Field with debris found 75 miles northwest of Roswell, New Mexico, in June 1947. (United States Air Force/AFP/Getty Images)
US plastic artist Peter Coffin's "Flying Saucer" flies over Ipanema beach on May 23, 2009, in Rio de Janeiro, Brazil. (Antonio Scorza/APF/Getty images)
Famous film actor and director Orson Welles answers journalists after causing panic throughout the United States with his radio broadcast "War of the Worlds," Oct. 30, 1938. (Staff/AFP/Getty Images)