How about two?
The mysterious big bang that has been the talk of Villa Rica and the surrounding three-county area since it occurred Friday night is still unexplained, though some think they know what it was and others say it wasn't the first unexplained sound in the area.
Some people have contacted the AJC saying they saw a large meteor around the same time as the noise, and others say a meteor can make a sonic boom if it gets close enough to the ground.
But if that's what made the loud sound heard in Carroll, Douglas and Haralson counties around 9:45 p.m., then what caused a similar noise two weeks earlier?
Several people have contacted the AJC to say that the recent explosion was preceded by a slightly quieter one on, or around, Nov. 13.
"It's so weird," said Sandra Harper, who lives in the Mirror Lake subdivision in Villa Rica, which was apparently ground zero for the latest blast. "Everybody got in a stew about this one but there was apparently no stew about the first one."
Harper said both explosions were hearty enough to rattle the windows on her home. After the first one, she ran to her deck, imagining that a house in the neighborhood had blown up from an ignition of natural gas.
She looked for smoke and waited for sirens. But when she saw and heard nothing, she went back inside. No one but her husband mentioned to her that they had heard it.
The next boom two weeks later caught the attention of far more people, it seems.
Douglas County Communication Director Wes Tallon said last weekend that "911 calls lit up" the switchboard after it shook houses across west Georgia.
Villa Rica authorities dispatched several police and fire units to the Mirror Lake neighborhood when the sound was first reported, but they found no smoke or damage.
Local authorities speculated that it was a sonic boom made by an aircraft exceeding the speed of sound, 761 mph. But a Federal Aviation Administration spokeswoman told the AJC that no commercial aircraft can travel that fast. Only military airplanes can make a sonic boom, and there are no military flight zones in the vicinity of the explosion and there was no record of military flights there at the time, said the FAA spokeswoman, Kathleen Bergen.
An avid star gazer who contacted the AJC said some meteors that made it close enough to earth could make a sonic boom. But given the relatively cloudless skies around the time of Friday's explosion, people should have seen it, Michael Covington, an amateur astronomer who has published several books about sky-watching, told the AJC last weekend.
"A really big meteor can make a sonic boom, but if it did, it would make a big flash of light," said Covington, who helps run a computer research program at the University of Georgia when he's not pursuing his hobby.
The local authorities didn't mention any reports of flashes overhead, but several people from the area have contacted the AJC saying they saw a bright light in the sky around the time of the explosion.
"It just looked like a big white ball," said Susan Burns, who lives on a sparsely populated ridge in south Paulding County. It was mottled, white and gray, like the moon, and it had a long tail, she said. "It was at least 10 times bigger than any other shooting star I've ever seen."
Burns lives near the Douglas County line and said the meteor appeared to fall straight down, to the west of her, and to the north of the Mirror Lake neighborhood. It was around 9:30 p.m. or 9:40 p.m., she recalled.
She found Covington after reading his comment in the AJC. They communicated by e-mail, and he told her that she must have seen the source of the explosion. It's possible that she wouldn't have heard anything because of the meteor's trajectory, he explained.
So maybe that's what happened. And maybe, in a freak coincidence, another big meteor fell in the same way, in the same place, unnoticed, two weeks earlier.
Or maybe there is still some other explanation out there.
Maybe it was a military pilot "who was having fun and not telling anybody," speculated Harper, the Mirror Lake resident.
Whatever it was, she said she hopes it doesn't return:
"I'll be concerned if, in two weeks, I hear the same sound again."
Comment: The Mirror Lake resident may have reason to be concerned:
See: Forget About Global Warming: We're One Step From Extinction!