Olbers, Heinrich Wilhelm Matthäus

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Olbers, Heinrich Wilhelm Matthäus (1758-1840), German physician and astronomer, born in Abergen (now part of Bremen). He was educated at the University of Göttingen and practiced medicine at Bremen. In 1779 he devised a method, still employed by astronomers, for calculating the orbits of comets. (Olbers discovered several comets, the first, named after him, in 1815.) In 1781 he identified Uranus as a planet rather than as a comet, as had previously been assumed. He discovered the asteroids Pallas in 1802 and Vesta in 1807 and first proposed that all asteroids are fragments of a shattered planet that formerly revolved around the sun. He observed, in 1826, that the night sky should be uniformly illuminated if the universe were infinite and homogeneous, with stars in every direction. This observation, called Olbers’s paradox, was only resolved with the discovery of the Redshift, along with the realization that stars have finite lifetimes.

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