My Mighty Meteorite

The Bad Astronomy guy (not a bad astronomer, himself) performed yet another random act of kindness. He mailed me something out of this world: a meteorite! Not the entire thing, mind you - but a bit of “Canyon Diablo” history. Here’s the first half of his accompanying “letter of authenticity,” with the second half of the meteorite’s decsription continued in this piece on my meteorite piece post…

No one knows what day it hit, what year, or even the millennium. It was probably about 30,000 years ago, but that’s as close as we know. Were people killed? Maybe; there may have been indigenous Americans then. Certainly a lot of animals never saw another sunrise.

On that day, a chunk of nickel-iron the size of a house and weighing 60,000 tons came screaming in from the sky. It was traveling at something like 11 kilometers per second - 40,000 kilometers per hour. Trailing smoke and flame, the meteoroid underwent vast pressure as it rammed through our thick atmosphere. A smaller object would have exploded in the air, raining fire down over a huge area. But this one was big enough to hit intact. When it slammed into the ground in northern Arizona, the energy released was equivalent to nearly 2 million tons of exploding TNT. In just a few seconds it carved a hole in the desert nearly a mile across and 600 feet deep, flipping over boulders that weighed many tons, and sending out a blast wave that traveled for hundreds of miles.

The meteoroid itself was vaporized by the energy of its impact. Probably only a small fraction intact. The rest rained down as droplets of molten iron over hundreds of square miles. The main mass buried itself in the crater, too deep to be accessible. The remainder blew out as small, twisted pieces that fell over the area.

Named after the area they fell, thousands of these Canyon Diablo meteorites have been found. They come in many shapes; some are long cylinders, some are just lumps, while others look more like exploded shrapnel (think Bugs Bunny sticking his finger in Elmer Fudd’s gun). [Second half of letter continued on My Meteorite Piece]

[tags]astronomer,asteroids,germanium,gallium,sulfur,asteroid,meteorite,meteorites,canyon diablo,outer space,cataclysm,iridium,phosphorus[/tags]