April 26, 2011 - Thousands of Meteorites Fall

No One is Hurt!

A Science is Born!

Some people worry that, since rocks sometimes fall from the skies, somebody might get conked in the head and die. That is not at all likely—as this story from 1803 makes non-painfully obvious:

On this day a couple of centuries ago, thousands of meteorites peppered the French town of L'Aigle. The meteorites ranged from one quarter ounce to 20 pounds—ouch!—but not one of them hurt anybody!

One fragment might have hit someone—but didn't hurt him. A wirepuller named M. Piche reported that he was hit on the arm by a small stone. He picked it up, curious, but immediately dropped it again because it was very hot.

There was also, reportedly, a close call: a stone fell on the pavement of the churchyard of St. Michel. It ricocheted off the pavement, bouncing upwards about a foot before coming to rest—right at the feet of the chaplain!

This 1803 event is an example of a meteoroid breaking apart as it sped through the Earth's atmosphere, so the 2,700 to 3,000 bits that landed could be said to be “meteorite fragments” rather than separate meteorites.

This event marked a turning point in understanding meteorites. In the 1700s it seemed fantastic, perhaps impossible, that a rock should fall from outer space. When people reported seeing a bright flash and then a stone falling out of the sky, and then the stone recovered, these events were investigated; each time scientists determined that a more reasonable explanation for the light and stone existed. A lightning strike on a larger rock was blamed, in one instance, and a volcanic eruption was blamed in another. 

The reports about thousands of stones falling on L'Aigle prompted the French Academy of Sciences to send Jean-Baptise Biot to check out the event. Biot studied the rocks and their location, and interviewed people in the town and nearby villages about the fireball they saw in the afternoon sky—and he came to the conclusion that the stones were of extraterrestrial origin—in other words, from space.

Other scientists, too, were able to study the rocks and Biot's data—he made the world's first “strewn field map”—and comparisons were made between these stones and others that had been seen falling from the sky. Soon consensus was reached in the scientific community: rocks could and did fall to the Earth from space. The science of meteorites began...

By the way...

Some people might read this story and think, wow, here's a great example of science getting things wrong for years! Those stuffy scientists with all their doubt about what people saw—they were Wrong! They said rocks couldn't fall from outer space—and they were WRONG!

Some people might even nod their heads and think, “See, anything's possible!”

But really this is a story of why science is so good at getting things right... A skeptical attitude that looks for multiple reasonable causes or known mechanisms for an unexplained phenomenon is a very good thing. Notice that, once evidence accumulated that shifted the probability to stones actually falling from space, scientists accepted that as the explanation. Scientists were then able to go back to old findings and reinterpret data, and of course modified their theories as new meteorite events occurred. 

Skepticism + openness to new ideas + ACTUAL EVIDENCE = reason + science.

And another “by the way”...

Apparently there are some stories about stones falling from the sky and hitting or even killing people, but there are very few confirmed claims. In 1954 a meteorite crashed through the roof of a home in Alabama, crashed into a radio, and bounced onto a woman named Ann Hodges. She was bruised but not badly injured. Also, a boy in Uganda claimed that a small stony meteorite fell onto his head. He was standing under banana trees, and the meteorite reportedly fell through numerous banana leaves before striking him on the head. As the stone was tiny and had hit so many leaves on its way, the boy felt no pain from the strike.

Check out these pictures of meteorites. Some are for sale! 

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