21 June 2013

Meteorite vs. meteor-wrong

A Minnesota farmer has harvested an interesting rock from his fields:
It’s a rare meteorite, at 4.6 billion years old — roughly the same age as our sun — and one of only nine or 10 that have been confirmed in Minnesota since European settlement...

Lilienthal, who raises corn, soybeans and beef cattle on about 2,000 acres, said he first spotted the rock half-buried in one of his fields in the spring of 2011. When he reached
down to remove it, he was amazed by how heavy it was for its size. It’s about 16 inches long, a foot wide and 2 inches thick, but it weighs 33 pounds — four times more than a typical rock would.

It also had a metallic clang, similar to that of an anvil, when tapped against other rocks.

[University of Minnesota Professor Calvin] Alexander estimates that he has looked at 5,000 rocks that people have brought him over the past 40 years, thinking they might be meteorites.  “We affectionately refer to them as meteor-wrongs,” he said.

He has confirmed two meteorites from other states, Alexander said, but this was the first new meteorite he’s ever seen from Minnesota. It contains more than 90 percent iron and about 8 percent nickel, with a unique crystalline pattern found only in meteorites.

2 comments:

  1. Sounds like the rate of confirmed meteorites needs study.
    The professor who confirmed my find (as much as you can without chemical analysis) said he had been checking "meteor-wrongs" for 20 years and I had the first he had seen (brought in by an amateur)

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  2. Good 'ole E. Calvin Alexander, he was my professor during hydrogeology field camp in Minnesota about 10 years ago!

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