The Nebra sky disk is a bronze disk about 30 centimeters in diameter and weighing 2.2 kg, having a blue-green patina and inlaid with gold symbols. These symbols are usually interpreted as the sun or full moon , lunar sickle and stars (including a cluster of seven interpreted as Pleiades ). Two golden arcs on the sides, interpreted as indicating the angle between the solstices, were added later. The final addition was another arc at the bottom, surrounded by many strokes (of uncertain meaning, variously interpreted as a solar barge with many oars, the Milky Way or a rainbow).
If the Bronze Age dating is accurate, Nebra's celestial disk represents the oldest concrete depiction of the cosmos ever known from anywhere in the world. In June 2013, it was included in the UNESCO "Memory of the World" register and recognized as "one of the most important archaeological finds of the twentieth century."
The disc was attributed to a site in modern Germany near Nebra , Saxony-Anhalt , and from the archaeological association to c. 1600 BC . Researchers originally assumed that the disc was an artifact of the Bronze Age Unetice culture , although a later Iron Age dating has been suggested .
The disc, two bronze swords, two axes, a chisel and fragments of spiral bracelets were discovered in 1999 by Henry Westphal and Mario Renner when they were searching for treasure with a metal detector. The archaeological artifacts are the property of the state of Saxony-Anhalt. The hunters were operating without a license and knew their activities were robbery and illegal. They damaged the drive with a shovel and destroyed part of the site. The next day, Westphal and Renner sold the entire treasure for 31,000 German marks to a dealer in Cologne. Over the next two years, the treasure changed hands in Germany and was sold for one million German marks. By 2001, information about its existence became public. In February 2002, state archaeologist Harald Möller acquired the disc in a police special operation in Basel from a couple who sold it on the black market for 700,000 German marks. The original seekers were eventually located. As part of a plea bargain, they brought police and archaeologists to the discovery site. Archaeologists excavated the site and found evidence to corroborate the robbers' claims. There are traces of bronze artifacts in the ground, and the soil at the site matches the soil samples found stuck to the artifacts. The disc and its accompanying finds are now preserved in the State Museum of Prehistory.in Halle , Saxony-Anhalt , Germany.
The two burglars were sentenced by the Naumburg court to four and ten months, respectively . They appealed, but the appellate court raised their sentences to six and twelve months respectively.
The discovery site is a prehistoric enclosure surrounding the top of a 252-meter high hill in the Siegelrod forest known as the Mittelberg ("central hill"), about 60 km west of Leipzig . The surrounding area is known to have been inhabited in the Neolithic period, and there are about 1000 burial mounds in the Siegelrode Forest.
The fence is oriented so that it looks as if the sun sets behind Brocken , the highest peak in the Harz mountains, about 80 km to the north-west at each solstice. Treasure hunters claimed that the artifacts were found in a hole inside the bank and ditch fence.