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.
Science and technology of the Han dynasty
The Han-era Chinese noted the passage of the same comet seen in Persia for the birth of Mithridates II of Parthia in 135 BCE, the same comet the Romans observed close to the assassination of Julius Caesar in 44 BCE, Halley's comet in 12 BCE, the same comet noted by Roman historian Cassius Dio (c. 155 – c. 229 CE) for 13 CE, and (what is now known to have been) a supernova in AD 185. For various comets discussed in the Han-era history books "Records of the Grand Historian" and "Book of Han", details are given for their position in the sky and direction they were moving, the length of time they were visible, their color, and their size.