Scientists have discovered part of the first Greek star catalog created by Hipparchus — thought by many to have invented the modern field of astronomy — hidden in a medieval parchment that had been reused for other puposes.

Scholars have been searching for Hipparchus’s catalogue for centuries. James Evans, a historian of astronomy at the University of Puget Sound in Tacoma, Washington, describes the find as “rare” and “remarkable”. The extract is published online this week in the Journal for the History of Astronomy. Evans says it proves that Hipparchus, often considered the greatest astronomer of ancient Greece, really did map the heavens centuries before other known attempts. It also illuminates a crucial moment in the birth of science, when astronomers shifted from simply describing the patterns they saw in the sky to measuring and predicting them.

The manuscript came from the Greek Orthodox St Catherine’s Monastery in the Sinai Peninsula, Egypt, but most of its 146 leaves, or folios, are now owned by the Museum of the Bible in Washington DC. The pages contain the Codex Climaci Rescriptus, a collection of Syriac texts written in the tenth or eleventh centuries. But the codex is a palimpsest: parchment that was scraped clean of older text by the scribe so that it could be reused.

Using modern multi-spectral imaging, the researchers were able to decipher the older text, and determined it was almost certainly written by Hipparchus and included his star measurements.

Read the whole article at the link. It is a fascinating detective story describing the origins of modern astronomy in western civilization.