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Phil Plait's Bad Astronomy: Bad News: The Salisbury ``Meteorite''
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Fire from the Sky

December 8, 2000

In the early evening hours of Monday, December 4, something fell from the sky in the small town of Salisbury, New Hampshire. Witnesses claim a fast-moving fiery object streaked down and impacted into David and Donna Ayoub's back yard, where it started two small fires. This much is considered to be fact.

After that, though, there's been plenty of speculation. A lot of the story supports the idea that it was a meteorite that did the damage. However, after looking into the case, I have concluded that it was a much more mundane - and Earthly - object.

The story appeared in the Concord Monitor on Tuesday December 5. The reporter, Stephanie Hanes, did a good job describing the situation, and even did some web searching to get data on meteors. The only (minor) quibble I have with her report is the line ``meteorites are essentially shooting stars that make it to the ground.'' The phrase ``shooting stars'' isn't terribly accurate, but neither is it wrong. A better statement would be that a meteorite is a bit of cosmic debris (a rock or chunk of metal) that doesn't completely burn up in our atmosphere and makes it down to the ground. Like I said, a quibble. Also, I believe she took this quotation directly from another website she found.

The story was picked up by several sources on the web, where I finally saw it. I was suspicious immediately, because small meteorites should not start fires. This is a very common misconception. Meteors are hot only for a short time, when atmospheric drag heats them up in a relatively complicated process. However, they slow so rapidly during this time that they reach terminal velocity-- at most a couple of hundred kilometers per hour-- while still high up. This gives them plenty of time to cool during the several minutes it takes to fall the rest of the way to the ground. As a matter of fact, the inside of the meteorite is still as cold as the ambient temperature of space, so many of them are covered in frost when found! So they won't cause fires, but they might give you frostbite.

A meteor moving fast enough to still be hot when it hit would also have carved a crater or pit into the ground about tens times the size of the impactor. No crater was found (some holes found on the scene were probably from burrowing animals, according to witnesses there).

I made some phone calls to the reporter and witnesses of the fall. It came out that the trajectory of the object was curved, and one witness likened it to a basketball thrown at a hoop. A meteor coming in would be falling straight down, or even at an angle, but not on an arc. Also, there was no evidence of the object on the ground after the fire was extinguished, as if it had burned itself out.

It sounds to me like this was some sort of fireworks, like a Molotov cocktail or Roman candle, launched from the nearby woods. That would explain the curved path, the fact that no one heard any noise, the reddish color described by witnesses (most meteors are yellow or white), the fires, and the fact that no remaining object was found.

It would have been nice for the folks involved if this really were a meteorite. It makes a great story, and the object itself could fetch thousands or tens of thousands of dollars, but it looks like this was no extraterrestrial visitor.

There are several places on the web talking about this story:

THE BIRDCAGE: ARCHIVE OF OTHER BAD NEWS ITEMS