Scholars believe they have found a piece of the earliest map of the night sky in a medieval parchment discovered in a monastery in Sinai, Egypt.
The catalog piece was analyzed in a study published in the peer-reviewed journal SAGE and is believed to be part of the lost Star Catalog written by the famous Greek astronomer Hipparchus who is known for making the earliest recorded attempt in history to fully catalog the stars.
The newly-found piece describes the stars and the measurements between them as can be seen in this translated excerpt:
"Corona Borealis, lying in the northern hemisphere, in length spans 9°¼ from the first degree of Scorpius to 10°¼8 in the same zodiacal sign (i.e. in Scorpius). In breadth, it spans 6°¾ from 49° from the North Pole to 55°¾.
"Within it, the star (β CrB) to the West next to the bright one (α CrB) leads (i.e. is the first to rise), being at Scorpius 0.5°. The fourth9 star (ι CrB) to the East of the bright one (α CrB) is the last (i.e. to rise) [. . .]10 49° from the North Pole. Southernmost (δ CrB) is the third counting from the bright one (α CrB) towards the East, which is 55°¾ from the North Pole."
This extract describes the Corona Borealis constellation's measurements as well as the stars contained within it and the measurements between them.
The researchers in the study compared the measurements in the catalog piece with the position of the stars in Hipparchus' time and a catalog written by Ptolemy and found that the measurements were either highly accurate or off by as little as one degree.
A more enriched picture of Hipparchus' work
James Evans, a historian of astronomy said that this Star Catalog gives us a more enriched picture of Hipparchus' work.
“It gives us a fascinating glimpse of what he actually did.”
James Evans
Hipparchus was an astronomer and mathematician who lived in the second century BCE and is considered to have made great contributions to astronomy as a mathematical science. He is known to have compiled an extensive map of the stars, but most of it has been lost over the centuries.