A one-pound meteorite discovered in the Sahara Desert in 2019 has provided the first definitive evidence of a long-lost planet destroyed more than four billion years ago.
According to researchers, this unprecedented discovery fundamentally alters the scientific understanding of the early solar system, suggesting that the destroyed parent body may have been as large as Earth’s moon.
Designated as Northwest Africa 12774, the meteorite is classified as an angrite. It is among the rarest and oldest volcanic rocks ever discovered on Earth, with only 68 confirmed specimens among more than 80,000 meteorites cataloged worldwide.
What distinguishes NWA 12774 from other angrites is a major discovery by geoscientist Aaron Bell and his colleagues at the University of Colorado Boulder. The team identified clinopyroxene crystals in the rock that are notably aluminum-rich, a clear indicator that they formed under extreme pressure.
The team’s analysis, published in the journal Earth and Planetary Science Letters, estimates that these crystals required pressures of at least 17.5 kilobars to form. This is equivalent to a pressure more than 17 times that at the bottom of the Mariana Trench—conditions that could not be generated inside a typical, small asteroid.
Using this extreme-pressure data, the researchers successfully inferred the minimum size of the parent body. Furthermore, the well-preserved edges and chemical integrity of the crystals suggest they formed at relatively shallow depths, as prolonged exposure to the deep interior heat of a hot planet would have completely eroded those features.
This geological evidence further supports a massive increase in the estimated size of the vanished world.