Germanmathematician and astronomer. In 1819 he calculated the orbit of a comet (subsequently named Comet Encke) that had been discovered by J. L. Pons, and found that its period was less than 4 years, still the shortest known. In 1837 he became the first to observe the gap in Saturn's A Ring, since named the Encke Division. He calculated the Sun's distance from observations of the transits of Venus in 1761 and 1769.
Subjects: Astronomy and Astrophysics.