A hidden star catalog on an ancient manuscript attributed to Hipparchus
Credit: Early Manuscripts Electronic Library/Lazarus Project, University of Rochester

Scholars studying Biblical texts have made an almost unimaginable find—fragments of a lost star catalog compiled by the ancient astronomer Hipparchus. Hipparchus’s work represents the earliest known project to catalog the entire night sky. The find is an example of a palimpsest—a manuscript that has been written over with other writings. The discovery was announced in the fall of 2022. 

The lost fragments were discovered by researchers examining a text taken from the library of St. Catherine’s Monastery, a Greek Orthodox monastery on the Sinai peninsula in Egypt. That text was written during the Middle Ages, a period of history that lasted form about the 400’s through the 1400’s. 

The text was written not on paper, but on a specially prepared animal skin called parchment. However, parchment and other materials could be rare in the Middle Ages. For this reason, scribes sometimes scraped the surface of the parchment, clearing the page for a new manuscript. In many cases, the scraped away writing can still be detected, forming a type of hidden manuscript called a palimpsest. 

In 2012, a biblical scholar asked his college students to study the text beneath the manuscript, hoping to find earlier Christian writings. But one student spotted an astronomical passage often attributed to the ancient Greek mathematician Eratosthenes. 

In 2017, researchers at the University of Rochester in New York analyzed the pages using multi-spectral imaging. They took 42 photos of each page at various wavelengths of light. A computer algorithm then combined the various images to search for hidden markings. The researchers discovered myths about the stars’ origins compiled by Eratosthenes, along with a poem about the constellations. 

During the COVID-19 pandemic, the house-bound scholar passed the time re-examining the images. He was surprised to find what appeared to be stellar coordinates, numbers that can be used to measure the position of a star in the night sky.  

Using radiocarbon dating, the coordinates were determined to be written in the 400’s or 500’s A.D. However, the way they were written suggested that they might have been copied from Hipparchus. Moreover, astronomers know that the stars appear to change position over time due to a wobble in Earth’s axis, an effect called precession. The coordinates were so detailed that scholars could thus determine that they were taken in 129 B.C., during Hipparchus’s life. 

The oldest surviving star catalog comes from a work called the Almagest by the astronomer Ptolemy, compiled in the 100’s A.D. Hipparchus’s earlier catalog is mentioned in ancient sources. But with no surviving evidence, it was thought to be lost forever or even never to have existed. 

The new discovery sheds an amazing light on Hipparchus’s work. Compiled nearly 2,000 years before the invention of the telescope, his catalog would have required countless hours of measurement with a sighting tube or a device called an armillary sphere. For now, only a few fragments remain, but scientists hope that they will help to identify other fragments of Hipparchus’s work in other manuscripts. 

June 20, 2014

The sounds of celebrations welcoming the summer solstice at Stonehenge in England thousands of years ago might have included rock music. If so, the music made from striking the huge stones used to construct the monument might explain why ancient Britons went so far afield to find the stones. People who gather at the valued World Heritage site for the arrival of the summer solstice tomorrow, however, will almost certainly have to content themselves with beating drums and singing.

The ancient ruin of Stonehenge, which lies on the Salisbury Plain in Wiltshire, consists of huge, rough-cut stones set in a circle. Archaeologists think that ancient Britons constructed the site as a gathering place and religious center, particularly for ceremonies linked to the solstices, the times of the year that mark the beginning of summer and winter. In fact, the paved avenue at Stonehenge lines up with the sunrise on the summer solstice. Thousands of people continue to gather at the site twice a year to celebrate the solstices.

Stonehenge was probably used as a tribal gathering place and a religious center by ancient inhabitants of England. It was built between about 2800 and 1500 B.C. The drawing shows what scholars believe was the original arrangement of the monument's huge stones. (Aerofilms)

One of the many mysteries of Stonehenge is why its ancient builders used rocks from hundreds of miles away for the inner ring–despite the presence of rock deposits much closer. Stonehenge’s inner stones, called bluestones, were quarried some 245 miles (395 kilometers) away in the Preseli Mountains of Pembrokeshire in southern Wales. After quarrying, the stones were dragged to the sea, loaded onto barges, and floated up Hampshire’s River Avon to near Stonehenge. For the ancient Britons, this was no small effort. The bluestones are massive, with some weighing up to 4 tons (3.6 metric tons).

Now researchers from the Royal College of Art in London have suggested an answer: The rocks were chosen for the bell-like sounds they produce when struck. Such sounding stones, also called lithophones, are often associated with healing rituals and can be found throughout the world. In the United States, Ringing Rock State Park in Pennsylvania is known for the chime-like qualities of its ancient boulders. Stonehenge’s bluestones, like the Pennsyvania boulders, are diabase rocks, dense, fine-grained igneous rocks with deposits of iron and magnesium. The volcanic rocks spent some 170 million years cooling below ground, explained geologist Lawrence L. Makinconico of Lafayette College in Pennsylvania. “When they cool, it’s something like forging a cast-iron bell,” he told The New York Times.

Additonal World Book articles:

• Avebury
• Megalithic monuments
• History of the United Kingdom (Prehistoric Britain)
• Archaeology (1966) (a Back in Time article)
• Cahokia: Mysteries in the Mounds (a Special Report)
• Reading the Sky: Early Places of Astronomy (a Special Report)

To hear sounds made by rocks in the Preseli Mountains, where Stonehenge’s bluestones were quarried, go to:

http://www.landscape-perception.com/acoustic_mapping/