News > Ball lightning theory could help explain UFO sightings
On 16 May 2006, a fine and clear Brisbane night was interrupted by the sudden appearance of at least three extraordinarily bright fireballs racing across the sky. On the same night, just after one of the fireballs had passed overhead, a farmer 120km west of the city reported seeing a luminous green ball rolling down a slope of a mountainous ridge known as the Great Divide.
One of the more popular explanations for these two strange visitations was, inevitably, that strange extraterrestrial forces were at work, in the form of UFOs. But according to a paper recently published by Australian astrophysicist Stephen Hughes, the events had nothing to do with little green men. Instead he puts forward the hypothesis that the strange green ball was ball lightning, and that the earlier appearance of the fireballs might go some way towards explaining this rare and little-understood phenomenon.
According to Dr Hughes, the fireballs, which are exceptionally bright meteors, similar to but larger than shooting stars, could have caused an electrical connection that triggered the ball lightning. He mooted the idea that when a meteor descended through the upper atmosphere – known as the ionosphere – it may have created a brief conductive connection between the ionosphere and the ground, causing sufficient electrical charge to enter the ground for the subsequent discharge to form a plasma ball.
Dr Hughes believes that similar electrical phenomena could provide the explanation for many a past UFO sighting. "If you put together inexplicable atmospheric phenomena, maybe of an electrical nature, with human psychology and the desire to see something - that could explain a lot of these UFO sightings," he told the BBC.