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.
Halley's Comet
Two Space Shuttle missions—the ill-fated STS-51-L (ended by the "Challenger" disaster) and STS-61-E—were scheduled to observe Halley's Comet from low Earth orbit. STS-51-L carried the Shuttle-Pointed Tool for Astronomy (SPARTAN-203) satellite, also called the Halley's Comet Experiment Deployable (HCED). STS-61-E was a "Columbia" mission scheduled for March 1986, carrying the ASTRO-1 platform to study the comet. Due to the suspension of America's manned space program after the "Challenger" explosion, the mission was canceled, and ASTRO-1 would not fly until late 1990 on STS-35.