Werner Landgraf
He also developed a method of eliminating systematic errors in positioning brighter comets that resulted in a more accurate prediction of the Halley's Comet. A recalculation of the path of Halley's comet to 2317 BC confirmed that the Greeks had already seen the comet on 466 B.C.
He discovered seven minor planets including 3683 Baumann, 4378 Voigt (named after Hans-Heinrich Voigt), 9938 Kretlow and 4349 Tibúrcio at ESO's La Silla Observatory in northern Chile.
Giovanni Battista Audiffredi
The predicted reappearance in the middle of the century of Halley's comet intensified scientific interest in cometic orbits. The epoch was favored with a number of brilliant objects of this kind, and that of 1769 distinguished itself by its great nucleus and by the tail which stretched over more than half the sky. Audiffredi took observations of the positions of the comet and published his results under the title, "Dimostrazione della stazione della cometa, 1769" (1770).