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A meteorite found in the Sahara Desert could be a fragment of a destroyed sibling of Earth. The small planet might have been blasted to rubble when the solar system was young. Some of the planet’s remains could have been incorporated into the other rocky worlds, including Earth.
NWA 12774 is a one-pound meteorite that was found in northwestern Africa in 2019. It belongs to a rare class known as angrites. They account for less than one-tenth of one percent of all known meteorites. They’re also among the oldest meteorites – they formed more than four and a half billion years ago, when Earth and the other planets were still taking shape.
Based on the composition of the meteorite alone, a team of researchers concluded that it was a fragment of a larger body that was disrupted during the early solar system. When the scientists included the structure of the meteorite, they determined that it came from near the surface of the parent body. That world would have been at least 2200 miles in diameter – as big as the Moon – and perhaps as big as Mars.
The parent world probably was destroyed in a collision with another large body. Such collisions probably were common in the early solar system. Earth probably smacked into a Mars-sized planet, for example. The impact blasted huge amounts of material into space, which eventually came together to form the Moon.
Script by Damond Benningfield
