X-ray Technology Unlocks Ancient Greek Star Map Hidden for Centuries
Scientists are currently reconstructing the oldest known map of the night sky, which had been thought lost to time for centuries, by employing advanced X-ray technology to reveal its hidden secrets. This remarkable map was created approximately 2,000 years ago and has spent hundreds of years concealed beneath the text of a medieval manuscript.
The Work of Hipparchus
The map is believed to be the work of the famous Greek astronomer Hipparchus, who lived from around 190 to 120 BC, long before the invention of the telescope. In 2022, analysis of a 6th-century monastery text first suggested that it might contain this ancient star map underneath its surface. Now, experts at the SLAC National Accelerator Laboratory in California are using X-rays to bring the ancient cosmos back to life in an unprecedented scientific endeavor.
'The goal is to recover as many of these coordinates as possible,' explained Victor Gysembergh, the lead scholar on the experiment, in an interview with KQED. 'And this will help us answer some of the biggest questions on the birth of science. Why did they start doing science 2,000 and more years ago? How did they get so good at it so fast? The coordinates we are finding are incredibly accurate for something that is done with the naked eye.'
Medieval Manuscript and Chemical Analysis
The medieval manuscript, known as the Codex Climaci Rescriptus, is thought to have been originally recovered from St Catherine's Monastery in Egypt. During the Middle Ages, parchment was an expensive material, so it was common practice to scrape clean the ink from existing documents and reuse them, which scientists believe likely happened in this case.
To closely analyze the parchment without causing damage, the researchers are utilizing an X-ray technique that can distinguish between different chemicals in the material. While the original text contained ink with traces of calcium, the overwritten version used ink rich in iron, allowing the team to visually separate the two layers effectively.
Discoveries and Future Prospects
The team has already made significant discoveries, identifying the word for 'Aquarius' and descriptions of 'bright' stars within that constellation. 'This new scan that we started…line after line of text showed up in ancient Greek from the astronomical manuscript,' Dr. Gysembergh reported. Researchers now plan to use this information to investigate how ancient astronomers achieved such precise results without magnifying instruments like telescopes.
A total of 11 pages are currently being scanned at the SLAC lab, with the entire manuscript comprising around 200 pages in total, though the remaining pages are scattered across various locations worldwide. In a video shared on the SLAC YouTube channel, the researchers describe the manuscript: 'This is the Codex Climaci Rescriptus, a set of ancient pages that hide a secret. But X-rays can reveal the truth. A long-erased star map lies beneath the text and hasn't been seen for hundreds of years…until now.'
Dr. Gysembergh added, 'Row by row, the ancient Greek text of the astronomical manuscript is gradually emerging. The opportunity to reconstruct the first map of the night sky is an extraordinary achievement for science.'
Preservation and Historical Context
To ensure maximum protection, the manuscript pages have been placed in custom-made frames, stored in humidity-controlled cases, and transported by hand. Light in the scanning room is also carefully controlled to prevent further ink fading. Hipparchus, often credited as the 'father of astronomy,' drew inspiration from Pre-Socratic philosophers, Aristarchus of Samos, Eratosthenes, Archimedes of Syracuse, as well as Babylonian and Egyptian sources.
Not much is known about Hipparchus's private life, except that he was born in Nicea, in modern-day Turkey, and is said to have died in Rhodes. All his writings, except for one, have been lost and are only noted in second-hand reports. Researchers speculate that Hipparchus's coordinates may have included observations of nearly every visible star in the sky, likely using a sighting tube that would have required countless hours of meticulous work, given the absence of telescopes at the time.
