Astronomy discoveries are not always made with telescopes or space probes. A dagger made of iron from the asteroid belt turned up in Egypt nearly a hundred years ago, though only in 2016 were scientists able to confirm its extraterrestrial origin.

The iron dagger was found, according to History.com, next to the mummy of the ancient Egyptian pharaoh Tutankhamen — better known today as King Tut. Along with another dagger made of gold, King Tut’s meteorite dagger was carefully placed in the tomb for the young pharaoh’s use in the afterlife, and buried with him around 1350 BCE.

Iron From the Sky

The date is significant, History.com explained, because the era around 1350 BCE was the height of the Bronze Age. Egyptian and Eastern Mediterranean technology of the day was capable of producing fine metalwork in bronze (an alloy of copper and tin), or gold. But the ability to produce high-quality artifacts from smelted iron did not appear until at least 1200 BCE, more than a century after Tutankhamen.

What the ancient Egyptians did know how to do, however, was make fine objects — such as King Tut’s meteorite dagger — from iron that already existed in high-purity form. And they knew that iron of this quality fell from the sky. Egyptian hieroglyphic writing even had a special symbol meaning “iron from heaven,” reported Discover magazine.

A Precious Metal in One of the Greatest Archeological Discoveries

This pure meteoric iron was a rare and precious material, worth more than its weight in gold — making King Tut’s meteorite dagger a fitting offering to place in the tomb of a pharaoh.

As History.com explained, the meteoric origins of the dagger have been suspected since its discovery beside Tutankhamen’s mummy in 1925. Until recently, however, there was no way to test the actual composition of the dagger without destroying it — not a practical research project, given the unique archeological, historical and aesthetic value of objects from Tutankhamen’s tomb.

Efforts to determine the dagger’s composition in the 1970s and 1990s were inconclusive, even controversial. But more recently, a new technology called portable X-ray fluorescence spectrometry was called upon to examine the ancient technology of King Tut’s meteorite dagger.

Technology, New and Ancient

The spectrometry technology, according to History.com, allowed precise determination of the composition of the dagger without damaging or even touching the dagger itself. And tests showed the dagger to be composed of iron, nickel and cobalt, in proportions not found in Earth’s iron ore deposits, but typical of meteorites that originated in the asteroid belt.

In fact, the measurements of the King Tut meteorite dagger not only confirmed the extraterrestrial origin of its iron, but indicated that the precise composition of the dagger matches that of a meteorite found near the Egyptian seaport city of Marsa Matruh.

The meteorite, now called Kharga, was found in 2000, and contains a mixture of iron with 10.8 percent nickel and 0.58 percent cobalt — the same composition as the dagger. None of the ten other meteorites found in or near Egypt matched that particular composition.

Tutankhamen’s tomb is not only one of the world’s most famous archeological discoveries: It continues to be a source of astronomy discoveries, insights into ancient Egypt, and evidence of how iron technology gradually developed during the Bronze Age.