Peter Simon Pallas
The naturalist who brought a giant mass of iron and olivine from Siberia to St Petersburg, the first pallasite known to science.
Key facts
- Born
- 1741
- Died
- 1811
- Nationality
- German
- Field
- Naturalist and explorer
Peter Simon Pallas was born in Berlin and became one of the great scientific explorers of the eighteenth century. Invited to Russia by Empress Catherine the Great, he led long expeditions across the Russian Empire, describing its plants, animals, rocks and peoples. Several animals, including Pallas's cat, carry his name.
In 1772, at Krasnoyarsk in Siberia, Pallas was shown an extraordinary object. A mass of metal weighing roughly 700 kilograms had been found in 1749 on a mountain some way from the town and dragged down to a village by local people. It was a spongy network of iron filled with glassy, yellow-green crystals. Pallas recognised it as something unusual and arranged for it to be carried to St Petersburg, where it joined the collections of the Academy of Sciences.
It was this mass that Ernst Chladni wrote about in 1794, when he argued that such irons had fallen from space. Pallas himself did not make that claim, but he had preserved and described the specimen at the centre of the debate.
The crystals in the Krasnojarsk iron are olivine, and the iron around them is nickel-rich metal. Meteorites of this kind are now called pallasites in his honour. They are among the most beautiful of all meteorites, and they probably formed where the metal core of an early asteroid met the rocky mantle above it.