Extracts of long-lost 2,100-year-old star map found behind medieval manuscript

Hipparchus’ Star Catalogue. (Courtesy Museum of the Bible Collection)

What was once lost can be found.

Researchers discovered this to be true after uncovering extracts of a long-lost star map originally written over 2,100 years ago by one of history’s greatest astronomers.

Greek astronomer Hipparchus’s Star Catalogue is the oldest known attempt at calculating the positions of the shiny celestial objects. Written between 170 and 120 BCE, the only available text of the star map was found through the writings of astronomer and mathematician Claudius Ptolemy, who created his own catalogue 400 years after Hipparchus.

However, researchers at France’s Centre National de la Recherche Scientifique (CNRS) were able to use multispectral imaging technology to read fragments of the catalogue written behind the Codex Climaci Rescriptus, a Greek palimpsest manuscript with pages erased and written over.

In their findings, published in the Journal for the History of Astronomy on Tuesday, the researchers were able to determine Hipparchus’ calculations were composed in equatorial co-ordinates; the widely known system to determine the co-ordinates of celestial objects.

They also confirmed Ptolemy’s Star Catalogue is not a complete copy of Hipparchus’s as previously thought. Additionally, Hipparchus’s Star Catalogue is more accurate in comparison to Ptolemny’s as it has an accuracy within one degree of the actual known star co-ordinates today.

Lead researcher Victor Gysembergh told the journal of Nature the technology used to discover the star map can help uncover more details of thousands of other ancient manuscripts.

“This is just one case, that’s very exciting, of a research possibility that can be applied to thousands of manuscripts with amazing discoveries every time,” Gysembergh told the journal of Nature.

According to New Mexico’s Museum of Space History, Hipparchus was considered one of the greatest ancient astronomers and mathematicians in history. By using a dioptra, a thin tube to scan the sky, he was able to make his calculations to create the star map. He was also known to have been the first to use geometric models to calculate the motions of the stars.

Nicknamed the “Father of scientific astronomy and trigonometry,” Hipparchus also made one of the earliest calculations using trigonometry.