Picture this: you live in the town of L’Aigle in Normandy, France. You’re just going about your business on this day in 1803, when suddenly, rocks start to fall from the sky.
You’d notice, right? Well, it was the presence of a townful of witnesses to more than 3,000 stones falling from the sky that finally helped scientists confirm that meteorites came from space.
Although writing about meteorites goes even farther back than the Romans, writes French researcher Matthieu Gounelle, prior to the late 1700s nobody thought of them as something that needed scientific explanation. Like rains of less likely substances—including ”blood, milk, wool, flesh and gore,” according to historian Ursula Marvin—eighteenth-century rationalists with their fancy new scientific outlook thought the stories of rains of iron rocks weren’t real.
A physicist named Ernst Chladni had published a book in 1794 suggesting that meteorites came from space. Chladni was hesitant to publish, writes Marvin, because he knew that he was “gainsaying 2,000 years of wisdom, inherited from Aristotle and confirmed by Isaac Newton, that no small bodies exist in space beyond the Moon.”
His theory gained some credence during the last decade of the 1700s, Gounelle writes, as several important meteorite falls happened that decade. But it still was far from accepted wisdom. One weakness of Chladni’s work was that he didn’t actually visit the site of a meteor fall and interview witnesses, Gounelle writes.
But after the meteorites fell in l’Aigle, Jean-Baptise Biot, a physicist, went to analyze the event. Biot was a scientist whose resume also includes the first scientific balloon flight and pioneering work in the field of saccharimetry (a way to analyze sugar solutions). He was also a strong believer in the power of science communication, and his literary, dramatic report on the l’Aigle fall got notice in popular media as well as scientific circles, helping to lend credence to his theory. Because it relied on evidence from real witnesses, it had human interest value.
“Biot distinguished two kinds of evidence of an extraterrestrial origin of the stones,” Gounelle writes. First, the kind of stone that had fallen was totally different than anything else available locally—but it was similar to the stone from the Barbotan meteor fall in 1790. “The foundries, the factories, the mines of the surroundings I have visited, have nothing in their products, nor in their slag that have with these substances any relation,” Biot wrote.
Second, unlike earlier falls, there were a number of witnesses “who saw ‘a rain of stones thrown by the meteor,’” Gounelle writes. They were from different walks of life, and, Biot wrote, it would be ridiculous to think they had all colluded to describe something that hadn’t happened. “One can follow Biot’s enquiry, village by village, step by step,” writes Gounelle.
His report read like a story but had scientific rigor. And only a few months after it was published, Gounelle writes, the idea that meteors came from space was acknowledged in the scientific community.