How does the history of meteorites show the scientific method?

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Accepted Answer

The slow acceptance that stones fall from the sky, between about 1794 and 1803, shows how evidence, testing and careful investigation change scientific opinion.

The story of how scientists came to accept meteorites is an ideal case study for teaching how science works.

Initial scepticism. In the eighteenth century, many educated people dismissed reports of stones falling from the sky. Stories were often vague, came from rural witnesses and sounded like superstition. Some scientists suggested the stones were ordinary rocks struck by lightning. Scepticism is healthy in science, but here it led people to ignore evidence.

A new hypothesis. In 1794 the German physicist Ernst Chladni published a book arguing that fireballs and fallen stones and irons came from outer space. He collected eyewitness accounts and examined iron masses, including the Pallas iron found in Siberia. Many scientists rejected his ideas.

New evidence. In 1795 a large stone fell at Wold Cottage in Yorkshire, and it was exhibited in London. In 1802 the English chemist Edward Howard and the French mineralogist Jacques-Louis de Bournon showed that stones from different falls were similar to one another and contained nickel-bearing metal, unlike Earth rocks.

The decisive test. On 26 April 1803, thousands of stones fell at L'Aigle in Normandy. The physicist Jean-Baptiste Biot visited, interviewed witnesses, mapped where stones had fallen and reported to the French Academy of Sciences. His careful work convinced most scientists.

Lessons for pupils. Discuss the roles of observation, testing, peer review, reproducible chemistry and open-mindedness. Ask pupils which pieces of evidence were most persuasive and why.

How does the history of meteorites show the scientific method?

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