BUT medieval parchment in Greek Orthodoxy Monastery of Saint Catherine of Sinai there was a big surprise hidden in Egypt: under the Christian text, part of the alleged lost star catalog of the ancient Greek astronomer Hipparchusthe world’s first attempt at complete “mapping” of the night sky.

Scientists have been looking for the work of Hipparchus for centuries, so historians of astronomy have called rare and important discovery. The corresponding scientific publication was made in the journal History of Astronomy. “Journal of the History of Astronomy”according to nature.

The find proves that Hipparchus, who is considered the most important astronomer of ancient Greeceactually made a “map” of the heavens several centuries before such an attempt was made.

How researchers discovered the “hidden” text

The parchment belonged to St. Catherine’s, but most of its 146 sheets are now in the possession of the Museum of the Bible in Washington. On parchment is the Codex Climaci Rescriptus, a collection of Syriac texts from the 10th or 11th century. The code palimpsestwhich means that older text was written underneath.

Initially, this earliest text was also thought to be Christian. But when, in 2012, biblical text expert Peter Williams of the University of Cambridge asked his students to study the Codex, he unexpectedly discovered a paragraph in Greek attributed to another famous Greek astronomer, Eratosthenes.

In 2017, a new analysis was carried out using more modern technology. multispectral imaging by American researchers who photographed parchment pages at various wavelengths of light and then used computer algorithms to read the text hidden underneath.

Thus, astronomical material was discovered on nine pages, radiocarbon dated and analysis of the writing style. from the 5th or 6th century. The text contained, among other things, myths about the birth of stars by Eratosthenes, as well as parts of the well-known 3rd century poem “The Phenomenon”, which describes the constellations.

List of stars

What happened next was even more interesting as Williams determined the star coordinates in the text and began further analysis in collaboration with the historian of science Victor Giseberg of the French National Institute for Scientific Research (CNRS) and Emmanuel Sin of the Sorbonne University in Paris.

Thus, it turned out that on at least one page of the parchment they were given the exact coordinates of the stars at the four ends of the constellation Corona Borealis (Northern Halo). Strong evidence was also found that the source of these measurements was Hipparchus and that his calculations were made about 129 BC.

Until today, the only surviving star catalog from antiquity was that of an astronomer Ptolemy in Alexandria, Egypt in the 2nd century AD. His Almagest (or Mathematical Syntax) was one of the most influential scientific texts in history, presenting a geocentric mathematical model of the world that has been widely accepted for over 1200 years. Ptolemy, among other things, gave the coordinates of over 1,000 stars.

Hipparchus was a pioneer

However, there are many references in ancient texts that the first the one who made such stellar measurements was Hipparchus the Rhodesian (190-120 BC), three centuries before. Previously, Babylonian astronomers had measured the position of some of the stars, but only around the Zodiac, and Hipparchus was the first to do so. determined the position of the stars in two coordinates and tried to create a “map” of the entire night sky.

“This list of stars, which until now appeared in the texts almost as something hypothetical, has now become something very specific,” said astronomy historian Mathieu Ossendriever from the Free University of Berlin.

Researchers believe that Hipparchus’ original list, like Ptolemy’s, included sightings of almost every visible star in the sky. Due to the lack of a telescope, Hipparchus may have used some other observing instrument, such as a telescope. diopterand, in the words of Giseberg, of course, “would have spent endless hours of work on it.”

Hipparchus and Ptolemy

OUR Hipparchus-Ptolemy relationship this has always been a vague question. Some experts have gone so far as to say that Hipparchus’ star catalog never existed, while others, most notably the 16th-century astronomer Tycho Brahe, conversely argued that Ptolemy simply stole Hipparchus’ pre-existing measurements and passed them off as his own. own. .

Analysis of the discovered parchment text so far has led researchers to the initial conclusion that Ptolemy was not just copying Hipparchus’ elements. On the other hand, as they pointed out, the Hipparchus numbers for the positions of the stars (with a deviation of no more than one degree from the real ones) are equal to much more accurate from the successor of Ptolemy.

Hopes for further discoveries

According to historian of astronomy James Evans of the American University of Puget Sound, the discovery “enriches our image of Hipparchus and gives us a charming glimpse of what he really did.

According to him, his work was decisive, since it was a milestone in the “mathematization of nature”, that is, the transition from a simple description of natural phenomena to their measurement, calculation and prediction.

Hipparchus criticized his predecessors in astronomy for not caring about numerical precision. According to Evans, Hipparchus took advantage of the Babylonian tradition of precise astronomical mathematical observation, and thanks to him there was a “marriage” with the Greek geometric tradition, as a result of which “This is how modern astronomy really began”.

Researchers hope that as imaging techniques improve they will discover other stellar coordinates in said Code, some parts of which have not yet been read.

They also consider it possible that additional pages of the Hipparchus star catalog were preserved in the library of St. Catherine of Sinai, which contains over 160 palimpsests. Related research has already revealed unknown ancient Greek medical texts under Christian ones.

Source: RES-IPE