The astonishing accuracy of the Nebra Astrolabe - an ancient star map unearthed in 1999

Wikimedia Commons The history of the Nebra SkyDisk dates back approximately 1,60 years

The Nebra Sky Disk is believed to be the oldest hand-drawn map of the night sky by humans. Its history dates back 3,600 years to the late Bronze Age in Europe, and it can still be used to measure the angle of the sun at the winter solstice.

Thousands of years ago, ancient Europeans seemed to have intentionally buried it. By that time, they had been in use for about 200 years and had even been modified to hide certain stars and add symbols to help measure leap months.

But because treasure hunters illegally looted it from a German hillside in 1999, the Nebra astrolabe went unanalysed by professionals in the years after it left the ground, making it Europe's largest One of the great archaeological mysteries.

Some researchers believe the artifact is not as ancient as people thought.

The Nebra Disk was unearthed in 1999 on a mountain called Mittelberg near the town of Nebra in Germany, from which it was named. It was discovered as part of a treasure trove that included two axes, two swords and a chisel. But this was no ordinary find - the disc was dug up by treasure hunters.

Halle State Museum of Prehistory Aerial view of the Mittelberg site where the disk was discovered in 1999.

Their rough digging damaged the outer edge of the disk, resulting in the loss of a gold circle and a star. But that didn't stop them from selling it to illegal antiquities dealers in Switzerland. Expert guidance took 2002 to find it.

In 2004, Richard Harrison, professor of European prehistory at the University of Bristol, told the BBC: "When I first heard about the Nebra Disc, I thought it was is a joke, I actually think it's a fake"

"It's such a remarkable piece of work that it's not surprising to any of us that a clever forger was in the closet. ”

But once trained researchers got their hands on it, they were able to reveal its extraordinary significance.

The beauty of the Nebra Sky Disk is undisputed. Its bronze base has a teal patina, while the foreground is covered in gold leaf and depicts a crescent, sun or full moon, and 32 stars, including seven star clusters believed to represent the Pleiades star cluster.

Flickr/Annette Bouwan Nebra Skypan Visitor Center near Nebra, Germany.

The outer bands on either side represent the horizon, while the smaller arc at the bottom represents the "sun boat" that Bronze Age Europeans believed to be the arrival of daylight. There are regularly spaced holes on the outer rim, which may have been useful for attaching the disk to a piece of cloth and carrying it as a standard.

Most researchers believe that prehistoric humans used it as an astronomical clock, allowing them to judge when was the best time to plant or harvest crops by telling them when the winter and summer solstices occurred.

The theory gained support when Professor Wolfhard Schlosser of the University of Bochum measured the angle between the disk's golden arcs. It's 82 degrees - the same path the sun takes along the Mittelberg horizon during the winter solstice.

"The astronomical rules depicted would be unimaginable without decades of intensive observation," said Harald Meller, director of the National Museum of Prehistory in Halle, which houses the circle. plate.

"Before the discovery of the celestial disk, no one thought that prehistoric humans had such precise astronomical knowledge."

Found in the hilt of a sword found next to the celestial disk of Nebra Carbon dating of a piece of birch wood confirmed it came from 1600 BC. Later analysis by the Institute of Archeology in Halle confirmed the age of the disk at 3,600 years and found it was made of metal extracted from Bronze Age mines in Austria.

Halle State Museum of Prehistory Nebra Sky Disk and a large collection of Bronze Age artifacts found nearby.

The treasure itself is further evidence of Bronze Age provenance. In an interview with the New York Times, Maikel Kuijpers, a professor of European prehistory at Leiden University in the Netherlands, said: "We actually saw a lot of these so-called deposits, or 'bronze hoards,' in the Bronze Age."

< p> But not everyone agrees with these conclusions. Rupert Gebhard, director of the Bavarian State Archaeological Collection in Munich, said the disk is 1,000 years younger than the 3,600 years most people think it is.

He based this claim on the account of one of the treasure hunters, who said he had removed the item from another location. He also saw that the disks were more similar to Iron Age artifacts than Bronze Age artifacts.

"The site in Mittelberg is outdated," Gebhard said. "We thought it was worthwhile to look around a new site."

However, no matter which way the science leads, Wolfgang David, executive director of the Frankfurt Archaeological Museum, is certain of one thing: < /p>

"Controversial discussions of issues that have yet to be conclusively clarified will spark new investigations, especially at Halley, and spur research progress."