This article originally appeared on Motherboard.
Since it was discovered in 1900 by divers off the Greek island of Antikythera, a complex clockwork device dubbed the "Antikythera Mechanism" has mystified everyone from archaeologists to UFO enthusiasts.
Theories have ranged from it being a simple clock, to baroque digressions about how it was gifted to humanity by aliens. All along, researchers have been piecing together the Mechanism's real use by deciphering its ancient Greek inscriptions, and their discoveries are as striking as any theory.
Sophisticated digital scanning done over the course of a decade indicates the Antikythera Mechanism was "a kind of philosopher's guide to the galaxy, and perhaps the world's oldest mechanical computer."
The discovery indicates that the Greeks of around 200 BC were capable of remarkably sophisticated and advanced technological innovation, perhaps even thousands of years ahead of its time.
"These very small texts are a very big thing for us," researcher Alexander Jones told the Associated Press. "It's a lot of detail for us because it comes from a period from which we know very little about Greek astronomy and essentially nothing about the technology, except what we gather from here."
The functions of the Antikythera Mechanism, which the research team described as essentially a teach tool, were surprisingly detailed. The machine tracked the movements of the sun and the Moon, their positions within the Zodiac, and the positions of the five known planets visible to the Greeks: Mercury, Venus, Mars, Jupiter and Saturn. The Mechanism also predicted solar eclipses.
Research teams began looking closely at the device in 2004, with an eye toward truly understanding how it worked. With x-rays and fine-tuned scanning technology they sifted through 82 pieces, gaining a richly detailed understanding of the artifact's true nature. According to team member Mike Edmunds, it wasn't in "the realm of executive toys," but a much more serious tool.
Although researchers now know more than ever about the Antikythera Mechanism, there is still a lot to learn. The ancient shipwreck where the known fragments were found 115 years ago still sits about 150 feet under the surface of ocean and archaeologists are searching it today. The team that revealed a new understanding of the device hopes that more pieces will be recovered. Perhaps even another mystery machine.