What is the freaky glowing orange orb that's been spotted on Route 66 for more than a century?

For more than a century, travelers on Route 66 have reported seeing a weird glowing orange orb around the intersection of Missouri, Kansas, and Oklahoma. The otherworldly orb, called the Hornet Spook Light, is usually seen on a short rural road just off 66 that's nicknamed the Devil's Promenade.

According to a 2006 Joplin Globe article, "during World War II, the Army Corps of Engineers spent some time investigating the light and concluded that it was a "mysterious light of unknown origin."

Some dismiss the Spook Light as car headlights in the distance, but other witnesses say that's simply not possible.

From the BBC News:

"I doubt it was car headlights," countered [Quapaw Nation elder Grace] Goodeagle. "I won't ever forget the experience. The light I saw bounced around and slowly approached my uncle's truck. It simply did not appear to be automobile headlights from a distance in any way."

"Some locals think the lights are caused by swamp gas," she added. But Andrew George, associate professor of biology at Pittsburg State University in Kansas, disagrees. "The landscape around the Hornet Spook Light is unlikely to produce luminescent gasses, which are thought to cause similar phenomena elsewhere," he explained.

Though he has not tested it himself, George backs the headlights idea. "The Hornet Spook Light is almost certainly caused by vehicle headlights on the larger roads a few miles to the west," he said. "The unusual appearance and movement of the light probably result from changes in air densities above the Spring River and the surrounding forests and fields. The light is refracted as it passes through the warmer and cooler air."

[Kansas Route 66 Visitors' Center volunteer Dean "Crazylegs"] Walker, like many locals, is not buying it. "No, it's not car headlights," he said. "It's just too far from the turnpike. There is just no way."