Researchers at the SLAC National Accelerator Laboratory in Menlo Park, California, have used X-ray beams to reveal once-hidden references to an ancient star map from a centuries-old document.
The ancient palimpsest—a portion of the Codex Climaci Rescriptus—has been revealed to contain fragmentary references to an ancient star catalog once used by the Greek astronomer Hipparchus. The ancient star maps in question were created by the astronomer as early as 150 B.C., copies of which were made several centuries later.
Now, the “lost” ancient writing has been made discernible as bright orange markings the X-rays have revealed, according to Minhal Gardezi, a physicist at the University of Wisconsin–Madison who was involved in the research.
A “Phaenomena” Emerges
The text revealed by SLAC researchers comprises portions of the poem “Phaenomena,” which dates to around 275 B.C. and is attributed to the Greek poet Aratus of Soli. The copies of the poem the SLAC team studied had likely been made sometime in the 6th century, at which time the unknown scribe also included sections comprising appendices relating to the positions of stars in various constellations, which were a perfect match for work known to have been undertaken by Hipparchus.
Originally transcribed on portions of animal hide, the remnants of the ancient poem were held within Saint Catherine’s Monastery in Egypt’s Sinai desert for centuries. At some point between the 9th and 10th centuries, the original text on the palimpsest appears to have been erased and reused to record a series of monastic treatises, seemingly destroying the ancient scientific information the ancient record once contained.
SLAC’s particle accelerator has now revealed these “lost” portions of the ancient poem using powerful X-rays, making the invisible records from long ago visible again for the first time in centuries (images of which can be seen here).
In the past, very little from Hipparchus’s writings has been recovered, and most of our knowledge of the ancient Greek astronomer stems from secondhand sources. Based on such information, scholars are aware that he can be credited with the creation of one of the earliest star catalogs, as well as early mathematical innovations that include the invention of trigonometry.
The team’s discovery is important, since it offers a rare glimpse at such records from the ancient world, which were often recorded on perishable materials like papyrus, which seldom survive through the ages.
Going beyond even the surprise discovery of these ancient astronomical records, the SLAC team’s process reveals a promising new means by which researchers may be able to retrieve similar “lost” information from surviving ancient records, especially those kept on more rugged materials that were often reused throughout time.
The recent discovery represents a veritable cornucopia of ancient information related to a crucial period in the emergence of science close to two millennia ago. However, this is not the first indication that traces of earlier ancient writing had been present on the palimpsest. In the past, earlier use of advanced imaging techniques had already shown that some form of writing was discernible.
Hellbound and Down 