If you saw a bright flash of light in the sky about 1 a.m. Monday, it wasn't a leftover firework. It was a meteor.

And a pretty impressive one at that.

Michael Gaines, who lives near the Costco on Hempstead Road, had gotten home from the Long's Park Patriotic Concert a few hours earlier and saw the flash from his porch.

With an interest in astronomy, Gaines knew that it wasn't a stray Fourth of July sparkler.

"It was a lot brighter than fireworks," said Gaines, who realized he was seeing the fireball of a large meteor. "You could see remnants, little fragments - something was moving from right to left across the sky."

Mike Smith of the North Museum, who writes the Cosmic Mike column for this newspaper, said Gaines was not alone in spotting the sky show.

"There have been many reports of people sighting what can be called a fireball, a large (meteor)," he said.

According to a story in the Baltimore Sun, geologists said that the object would have to be a few yards in diameter to have attracted the attention it did.

Based on witness descriptions, the object appeared at approximately 1:05 a.m. and flew south to north over central Maryland and southern Pennsylvania before vaporizing at 1:10 a.m.

One man, camping on the Susquehanna River in Delta, wrote on the Baltimore Sun's weather blog: "It was as if it were daylight outside. ... Approximately 60 to 90 seconds after the sky had lit up, we heard a thunderous series of sonic boom sounds accompanied by tremors."

Gaines, along with a number of other people in Pennsylvania and Maryland, recorded what they saw on the Web site amsmeteors.org.

"For Lancastrians to be able to see a fireball, I'd say that's rare," Smith said. "The majority are really small and burn up before they touch surface."

Meteors, which become meteorites once they hit the ground, are leftover debris from comets and are scattered along the comet's orbit around the sun.

Some meteor showers are predictable. For example, the Perseids peaks in mid-August every year. Others, like the one spotted Monday, are a surprise.

"Quite a few reports say it came down somewhere, but I don't know if they'll find it," Gaines said. "That's a lot of land to cover for something that was probably the size of a fist when it landed."

Intelligencer Journal/Lancaster New Era