World's Oldest Star Map Has Been Found in St. Catherine's Monastery

Within the library of St. Catherine’s Monastery in South Sinai - the oldest continuously-running Christian monastery in the world - researchers have uncovered a fragment of history’s oldest complete star map, penned by ancient Greek astronomer and mathematician Hipparchus.

Hipparchus is considered to be the greatest astronomer in ancient Greece, and so researchers had been searching for his catalogue of stars for centuries. The manuscript in St. Catherine’s Monastery appeared to be something completely different; the pages contained a collection of 10th or 11th century Syriac text called the Codex Climaci Rescriptus. But as it turned out, it wasn’t just that - the pages were a palimpsest, or a parchment in which previous text was wiped clean so that it can be reused.

But much like scribbling your pencil over recently erased writing, it was possible to discover what was erased from a palimpsest. Researchers from the University of Cambridge, the University of Rochester in New York, the Early Manuscripts Electronic Library in Rolling Hills Estates, California and the French national scientific research centre CNRS in Paris worked together to find layers of writing that had been wiped away. Amongst them were the coordinates for the constellation Corona Borealis, and by comparing these precise coordinates with how the night sky would have been arranged in antiquity, the researchers found that the coordinates would have been made in 129 BC - right when Hipparchus was making his revolutionary cosmic calculations.

An excerpt of the discovered document was recently published in the Journal for the History of Astronomy, and is available online.