3,000-piece meteorite shower helps launch meteorology

The meteorite shower that hit the town of L'Aigle in France in 1803 provided convincing evidence of the existence of extraterrestrial rocks, marking the beginning of meteoritic science.

Simulation of the 1783 meteor shower. Photo: Wellcome Collection

Before the 1800s, scientists were skeptical about meteorites. Despite historical records of them dating back to Roman times, the idea of ​​rocks falling from the sky seemed implausible to experts at the time. Most believed they originated on Earth, perhaps from volcanic activity, or formed when dust particles in the atmosphere coalesced during lightning strikes, as proposed by the 17th-century scientist René Descartes.

In 1794, German physicist Ernst Chladni challenged popular belief and proposed in a book that meteorites were extraterrestrial in origin. According to Chladni, they were fragments scattered throughout the solar system and never coalesced into planets. This would explain the high velocity and intense luminosity of falling rocks as they entered Earth's atmosphere. Chladni also pointed out the correlation between the "fireballs" that had been observed and the cases of falling rocks, along with the physical similarities in the rocks collected after the fall.

Chladni’s theory was controversial because it contradicted both Isaac Newton’s and Aristotle’s views on celestial bodies. His claims also challenged the prevailing belief that there was nothing beyond the Moon other than stars and planets. Some embraced his theory that meteorites originated from extraterrestrial sources, but others rejected it in favor of alternative explanations involving volcanic activity, turbulent ocean currents, or lightning striking iron ore.

In the years after Chladni's work was published, astronomers began to make groundbreaking discoveries that added weight to the case for asteroids in the Solar System. In 1801, astronomer Giuseppe Piazzi discovered Ceres, marking the first asteroid discovery. In 1802, Heinrich Olbers discovered the asteroid Pallas. Also in that year, two chemists, Jacques-Luis de Bournon and Edward C. Howard, studied the asteroids closely, finding that they had chemical compositions and mineral contents different from those of Earth's rocks. These new discoveries gradually strengthened the view that meteorites came from extraterrestrial sources.

In the early afternoon of April 26, 1803, the town of L'Aigle in Normandy, France, experienced a remarkable event when more than 3,000 meteorite fragments fell. The French Academy of Sciences quickly dispatched a young scientist, Jean-Baptiste Biot, to investigate the phenomenon. Biot conducted thorough field research, collected various eyewitness accounts, analyzed rock samples from the surrounding area, and eventually presented convincing evidence of the extraterrestrial origin of the fallen rocks.

A fragment of the L'Aigle meteorite. Photo: Marie-Lan Tay Pamart/Wikimedia Commons

First, Biot noted that the composition of the stones was significantly different from any local material, but had many similarities to stones found in previous meteorite falls, suggesting a common extraterrestrial origin.

Biot then interviewed several observers who independently attested to having seen the meteorite shower. These people came from different backgrounds, and Biot believed that they could not have collaborated to fabricate a description of an event that did not occur. Biot's research confirmed that the L'Aigle meteorite stones were of extraterrestrial origin, marking the beginning of meteorology.

Today, a fragment of the L'Aigle meteorite, along with Angers, another meteorite that fell in France 19 years later, is preserved in a special room at the Muséum d'histoire Naturelle d'Angers, a French natural history museum. These meteorites are a tangible reminder of a pivotal moment in the history of science, when skepticism gave way to acceptance and meteorology became a mainstream field of study.

Thu Thao (According to Amusing Planet )

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