1758-1840

German astronomer and physician who developed a method for calculating cometary orbits. He suggested a theory for why the tails of comets point away from the sun and discovered the second and third known asteroids—Pallas (1802) and Vesta (1807). Astronomers at the time assumed an infinite universe in which the night sky should be covered with stars, and his formulation of why, in that case, the night sky is dark became known as Olbers' Paradox.