In 1803 he investigated the meteorite fall at L’Aigle in France. The Swiss physicist Marc Auguste Pictet-Turretin (1752–1825) had suggested that meteorites fell from the sky, and E. F. F. Chladni had speculated that they were the remains of a shattered planet, but the idea was generally dismissed. By questioning witnesses of the fall and analysing specimens of meteorites and of the ground where they lay, Biot was able to demonstrate that meteorites have a cosmic origin. This was the first properly scientific study of meteorites.