Heinrich Olbers Discovers the Asteroid Pallas

Heinrich Olbers Discovers the Asteroid Pallas

On March 28, 1802, the German astronomer Heinrich Wilhelm Matthaus Olbers detected the asteroid Pallas while researching the orbit of the asteroid Ceres. Pallas is the second largest of the asteroids and is roughly 300 miles in diameter. It takes approximately four and a half Earth-years to orbit the Sun.

Pallas, named for the Roman goddess of wisdom, is found in the solar system's asteroid belt, which lies between the orbits of Mars and Jupiter. The belt's origin is unknown, although the bulk of current astrophysical theory holds that it contains the fragments of a planetary body that was unable to completely form in the early days of the solar system. The first asteroid in the belt to be discovered was Ceres (1801), which also happens to be the largest asteroid of them all at nearly 600 miles in diameter. Pallas was the second asteroid to be discovered, in addition to being the second-largest.

A physician by profession, Olbers (1758– 1840) was an amateur astronomer of distinction long before he discovered Pallas. In 1779 he invented a method for plotting the orbits of comets which is still in use today. In addition to Pallas, Olbers also discovered Vesta in 1807, the fourth asteroid to be found and the third-largest, being just a few miles in diameter smaller than Pallas. Today there are thousands of known asteroids in the Asteroid Belt.