Earth and the Moon
Meteors and Meteorites
How did scientists learn that meteors and meteorites come from outer space?
In 1714 English astronomer Edmund Halley (1656–1742) carefully reviewed reports of meteor sightings. From the reports, he calculated the height and speed of the meteors, and deduced that they must have come from outer space. Other scientists, however, were hesitant to believe this notion, thinking instead that meteors and meteorites were either atmospheric occurrences like rain, or debris spewed into the air by exploding volcanoes.
In 1790 a group of stony objects showered part of France. Georg Christoph Licht-enberg (1742–1799), a German physicist, assigned his assistant Ernst Florens Friedrich Chladni (1756–1827) to investigate the event. Chladni examined reports of these falling stones, as well as records over the previous two centuries. He, like Edmund Halley, also concluded that the chunks of matter came from outside Earth’s atmosphere. Chladni guessed that meteorites were the remains of a disintegrated planet.
In 1803 in a series of loud explosions, more than two thousand meteorites fell to Earth onto French territory. Jean-Baptiste Biot (1774–1862), a member of the French Academy of Science, collected reports from witnesses as well as some of these fallen stones. Biot measured the area covered by the debris and analyzed the composition of the stones, showing that they could not have originated in Earth’s atmosphere.