New evidence for ancient Greek astronomer Hipparchus’ lost Star Catalogue has come to light thanks to multispectral imaging of a palimpsest manuscript and subsequent decipherment and interpretation. This new evidence is the most authoritative to date and allows major progress in the reconstruction of Hipparchus’ Star Catalogue. In particular, it confirms that the Star Catalogue was originally composed in equatorial coordinates. It also confirms that Ptolemy’s Star Catalogue was not based solely on data from Hipparchus’ Catalogue. Finally, the available numerical evidence is consistent with an accuracy within 1° of the real stellar coordinates, which would make Hipparchus’ Catalogue significantly more accurate than his successor Claudius Ptolemy’s.
