Scholars may have just discovered a fragment of the world’s oldest star map. 

The map segment, which was found beneath the text on a sheet of medieval parchment, is thought to be part of the long-lost star catalog of the second century B.C. Greek astronomer Hipparchus, who made the earliest known attempt to chart the entire night sky. The fragment was concealed beneath nine leaves, or folios, of the religious Codex Climaci Rescriptus at St. Catherine’s Monastery in Egypt’s Sinai Peninsula.