Two Suns Setting? Scientists Offer Explanations of Chinese Video

March 7, 2011 — -- Early in the original "Star Wars" movie, there is a scene in which the restless young Luke Skywalker looks out at the two suns setting on his home planet of Tatooine.

It was a charming, exotic touch, and it was done simply. Two images of the earth's sun were superimposed next to each other.

Now, video of what looks like two suns setting has been broadcast by Chinese television -- and it's quickly spread all over the Web.

Click here to see the video, or watch in the video box in upper left.

Just what is it? An optical illusion? A practical joke? Or has Betelgeuse, the bright star in the constellation Orion, gone supernova, dooming us all? (That rumor made its way around the Web in January and had a lot of astronomers hurrying to calm people.)

Sorry. The explanations offered by scientists today are fairly down-to-earth.

"Many photographs are sent to me each year that look like the China sighting," said Les Cowley, who runs a British website called Atmospheric Optics. "Some have more than two suns. They are almost invariably artifacts, the result of shooting through windows or using plane filters on the camera."

"In brief," he said, "it is almost certainly a reflection owing to shooting through a window."

Several astronomers said ice crystals or air pollution can bend light -- but the resulting mirage is usually vertical -- one sun image above the other, instead of two side-by-side.

Michael Shara, an astrophysicist at the Richard Gilder Graduate School at New York's American Museum of Natural History, said he suspected "a very rare mirage caused by suspended ice particles, or a camera lens defect...or photoshop."

Geza Gyuk, director of the astronomy department at the Adler Planetarium in Chicago, said he was reminded of the old quotation, sometimes used by the late Carl Sagan, that "extraordinary claims require extraordinary evidence."

'Two Suns' Setting: Optical Illusion? Or Hoax?

"In this context, one short, low-resolution, and shaky video clip of unclear provenance, is not enough to draw any firm claims," he wrote in an e-mail to ABC News." I'd be comfortable neither with simply dismissing it out of hand nor with proclaiming that "there are optical phenomena unknown or unexplained by science." He wondered about a window reflection or a lens flare, and said it would be nice for people to look at the sky more often: "There are amazing atmospheric displays all the time and they are well worth looking at!"

Grant Petty, a professor of Atmospheric and Oceanic Sciences at the University of Wisconsin, said he had his doubts too, especially after January's story about Betelgeuse.

"The proximity of this seemingly inexplicable image of two suns to the story in question leads me to strongly suspect a deliberate hoax inspired by the story," he wrote in an e-mail, "but that's of course conjecture without knowing more about who shot the video and where."

At any rate, say the experts, the final explanation could be intriguing, or awfully mundane. Back to our regular lives. Nothing to see here....