Beth and Dan Curley were driving down Route 611 when the basketball-sized flame shot across the sky.

It was white when Dan spotted it. By the time Beth looked up, it had turned stoplight green. The flame died out a few seconds later.

"It wasn't far off in the sky - it was there," the Warrington woman said. "It was the coolest thing we've ever seen."

The Curleys, who saw the fireball from Route 611 near Bristol Road in Warrington, were among several people in Bucks County who said they spotted what appeared to be a meteor just before 10 p.m. Sunday.

According to NASA, a meteor is a bright streak of light that is visible when a chunk of space matter enters the Earth's atmosphere. No one who reported spotting the fireball Sunday saw it hit the ground, which would have made it a meteorite. Warrington police said they weren't aware of any meteor reports Sunday night, let alone any impact.

However, if it landed, it could have been anywhere. On an Internet message board, people reported seeing the ball of light from Coopersburg and Quakertown as well.

Bucks-Mont Astronomical Association president Dwight Dulsky did not hear about the sightings, but said spotting a meteor is not unusual in the days leading up to the annual Perseid meteor shower, expected this year on Aug. 12, which can produce up to 60 to 90 meteors per hour. Last Thursday night, he spotted five meteors in three hours with his telescope, he said.

Dulsky said the International Space Station - another bright, fast-moving object in the sky - was forecast on to fly over the Bucks County area around 10:15 p.m. Sunday.

"An experienced observer would never confuse a satellite with a meteor, but some folks might," Dulsky said in an e-mail.