THE GENESIS OF HIPPARCHUS’ CELESTIAL GLOBE

Abstract

The globe of Hipparchus is not preserved. For that reason, it has been a source of much speculation and sci

entific inquiry during the last few centuries. This study presents a new analysis of the data given in the

commentary on Aratus’ poem by Hipparchus, in comparison with other contemporary Babylonian and

Greek astronomical data, as well as their predecessors in the first millennium and their successors up to

Ptolemy. The result of all these studies are the following: i) although the data of Ptolemy and Hipparchus are

undoubtedly correlated, it is certainly also wrong to accuse Ptolemy having simply copied and transformed

it without correct citation; ii) although Hipparchus presumably observed most of his star catalogue with his

own instruments, we cannot neglect Babylonian influences. Hipparchus was educated in Greek astronomy

but, in his time, there are traces of Babylonian influences since at least two centuries. Since we are unable to

definitely prove that Hipparchus used Babylonian data, we are not sure if there are direct Babylonian influ

ences in his time or as a consequence of his education only. Finally, we present a virtual 3D–image showing

what the globe of Hipparchus might have looked like.