A recent study published in Earth and Planetary Science Letters presents compelling evidence of a massive protoplanet that existed in the early solar system approximately 4.5 billion years ago.Researchers from the University of Colorado Boulder analyzed the Northwest Africa 12774 angrite meteorite, discovered in the Sahara Desert.

Angrites are rare volcanic rocks dating back to the solar system's formation, with only 68 known specimens among over 80,000 meteorites found on Earth.This particular meteorite contains clinopyroxene crystals unusually rich in aluminum, indicating formation under extreme pressures exceeding 17.5 kilobars.Such conditions are impossible within small asteroids, suggesting the parent body had a radius of at least 1,000 kilometers.

Further analysis of crystal structures points to an even larger size, potentially up to 1,800 kilometers in radius, comparable to the Moon or approaching Mars' dimensions.This challenges prior assumptions that angrites originated solely from small asteroids due to their low silica content.

The discovery implies diverse evolutionary pathways for planetary bodies in the early solar system, with this protoplanet following a distinct chemical trajectory from Earth or Mars.Scientists speculate it may have been destroyed in a collision, with fragments contributing to other terrestrial planets.The findings highlight the value of re-examining existing meteorite collections for insights into solar system history.

Lead researcher Aaron Bell emphasized that these materials reveal fundamentally different ingredients and development processes than those of known planets.