Researchers have discovered behind medieval parchment, ctorn star catalog of the ancient astronomer Hipparchus
Researchers using multispectral imaging have revealed a hidden original text written in the manuscript Codex Climaci Rescriptus which came from the monastery of Saint Catherine in Egypt.
The hidden text appears to belong to Greek astronomer Hipparchus of Rhodium, ο οποίος συχνά αποκαλείται «πατέρας της αστρονομίας». Του αποδίδεται η ανακάλυψη της μετάπτωσης της Γης (πώς ταλαντεύεται στον άξονά της) και ο υπολογισμός των κινήσεων του Ήλιου και της Σελήνης, μεταξύ άλλων επιτευγμάτων.
Ο Ίππαρχος πιστεύεται επίσης ότι συνέτασσε έναν κατάλογο αστεριών, ίσως την παλαιότερη γνωστή απόπειρα χαρτογράφησης του νυχτερινού ουρανού μέχρι σήμερα, κάπου μεταξύ 162 και 127 π.Χ., με βάση αναφορές σε ιστορικά κείμενα.
Scholars have sought this list for centuries. Now, thanks to a technique called multispectral imaging, they've found part of that Hipparchus catalog of stars. It was hidden under Christian texts on medieval parchment, according to a newly published paper στο Journal for the History of Astronomy.
Multispectral imaging is a method that takes visible blue, green and red images of an object and combines them with an infrared image and an X-ray image. This technique can reveal small hints of pigment, as well as hidden patterns or writing under several layers of paint or ink.
For example, researchers previously used the technique to uncover hidden text on four pieces of papyrus found in the Dead Sea, previously thought to be unwritten.
And last year, Swiss scientists used multispectral imaging to reconstruct photographic plates created by French physicist Gabriel Lippmann, who pioneered color photography and won the 1908 Nobel Prize in Physics for his efforts.
The current work arose from research on the parchment Codex Climaci Rescriptus, which came from the monastery of St. Catherine in the Sinai Peninsula in Egypt. It consists of 11 individual manuscripts, with Aramaic texts of the Old and New Testaments and Greek text of the New Testament, and other content.
Τα κείμενα αυτά χρονολογούνται στον 6ο, 7ο και 8ο αιώνα, αντίστοιχα. Ο κώδικας φυλάσσονταν στο Westminster College στο Cambridge μέχρι το 2010, όταν ο Steve Green, πρόεδρος του Hobby Lobby, τον αγόρασε από τον Sotheby’s. Τώρα είναι μέρος της Πράσινης Συλλογής που εκτίθεται στο Μουσείο της Βίβλου στην Ουάσιγκτον, αν και μερικά φύλλα έχουν αποθηκευτεί αλλού.
It was common practice at the time to scrape off an old parchment for reuse. At first, scholars assumed that the earliest writing was more Christian texts. But when Peter Williams, a bibliographer at the University of Cambridge, asked his students to study the pages as a special assignment in 2012, one of them identified a Greek passage by the astronomer Eratosthenes.
This warranted further investigation, so Williams turned to scientists at the Early Manuscripts Electronic Library in California and the University of Rochester in New York to perform multispectral imaging of its pages. The technique revealed nine complete sheets dealing with astronomy, dating between the 5th and 6th centuries. Not only Eratosthenes' passage on the myths of the origin of the stars, but also a famous poem (Phenomena, circa 3rd century BC) describing constellations.
Williams spent much of his time during the pandemic lockdown studying the resulting images and one day noted that what he was seeing appeared to be the coordinates of the constellation Stefanos Voreios (Corona Borealis). He immediately contacted science historian Victor Gysebergh of the CNRS in Paris about his discovery. "I was very excited from the beginning," Gysembergh said in Nature. "It was immediately clear that we had star coordinates."
Gysebergh and his colleague, Emanuel Zingg of Sorbonne University, translated the one-page passage as follows:
Northern Stephen, located in the northern hemisphere, in longitude extends from 9°¼ of the first degree of Scorpio to 10°¼ in the same sign (i.e. Scorpio). In latitude it extends from 6°¾ from 49° from the North Pole to 55°¾.
Within it, the star in the West next to the bright leads (ie is the first to rise), being in Scorpio 0,5°. The fourth star to the east of the bright one is the last (i.e. rising) [. . .]10 49° from the North Pole. The southernmost is the third measurement from the bright to the East, which is 55°¾ from the North Pole.
But could this passage be attributed to Hipparchus? While cautious about definitive attribution, the authors cite several elements that seem to link the text to the Greek astronomer. For example, some of the data is recorded in an unusual way, but one that is consistent with the only other surviving work of Hipparchus.
And the authors were able to use astronomical charts to determine that the observations recorded in the text were likely made around 129 BC, when Hipparchus would have been working on his catalog.
So far, only the coordinates for the Corona Borealis have been recovered, but researchers believe it is very likely that Hipparchus mapped the entire night sky at some point, including all visible stars, just as Ptolemy later did treatise of "Mathematical Syntax” (Almagest). Many scholars believe that Hipparchus' list was one of the sources used by Ptolemy in writing his treatise.
In fact, scholars have found that Hipparchus's coordinate calculations were actually much more accurate than Ptolemy's, and correct to a degree. This was an amazing feat, given that the telescope had not yet been invented.
They hypothesize that Hipparchus probably used an optical tube called a diopter or a sphere to make his calculations. And they hope that other parts of the catalog of lost stars are still hidden in the monastery's library and will be found as imaging techniques continue to improve.