C/1980 E1

C/1980 E1 is a non-periodic comet discovered by Edward L. G. Bowell on 11 February 1980. C/1980 E1 is leaving the Solar System on a hyperbolic trajectory with a higher velocity than any other natural object ever observed.

Before entering the inner Solar System for a 1982 perihelion passage, C/1980 E1 had a barycentric (epoch 1950-Jan-01) orbit with an aphelion of 74,300 AU (1.17 light-years), and a period of approximately 7.1 million years.

As the comet was approaching perihelion on December 9, 1980, it passed within 0.228 AU of Jupiter, which accelerated the comet briefly giving an (epoch 1981-Jan-09) eccentricity of 1.066. The comet came to perihelion on March 12, 1982, when it had a velocity of 23.3 km/s (52,000 mph) with respect to the Sun. Since the epoch of 1977-Mar-04, C/1980 E1 has had a barycentric eccentricity greater than 1, keeping it on a hyperbolic trajectory that will eject it from the Solar System. Objects in hyperbolic orbits have negative semi major axis, giving them a positive orbital energy. The Minor Planet Center does not directly list a semi-major axis for this comet.