A shattered world revealed by a rare desert meteorite
In short: Researchers have identified the initial tangible proof of a giant protoplanet that once circled the nascent Sun before a violent impact destroyed it. This lost world, potentially as large as Mars, followed a geological path entirely different from any other known terrestrial planet in our solar system.
The discovery centers on a rare meteorite known as Northwest Africa (NWA) 12774, found in the Sahara Desert. This particular rock is an angrite, among the solar system's most ancient volcanic stones, created merely a few million years after the system's birth 4.56 billion years ago. Angrites are remarkably scarce; from the 80,000-plus meteorites located on Earth, just 68 are classified as this type.
For years, the chemistry of angrites puzzled researchers because they contain very little silicon dioxide (silica), a primary ingredient in Earth, Mars, and other rocky planets. Due to this silica deficiency, experts formerly believed these meteorites came from tiny asteroids measuring under 200 kilometres (124 miles) in radius. However, analysis of NWA 12774 revealed clinopyroxene, a mineral common in Earth's crust and mantle, which was exceptionally rich in aluminum.
The aluminum content is a critical indicator of extreme pressure. Researchers calculated that the clinopyroxene required at least 17.5 kilobars of pressure to form. To provide context, the pressure found at the base of the Mariana Trench—Earth's lowest point—reaches only roughly 1 kilobar. A small asteroid could never have produced such immense pressure internally. Rather, the evidence implies that a radius of no less than 1,000 kilometres (621 miles) was required for the parent body, showing it was a huge planetary embryo comparable to Mars or the moon in scale.
This finding is significant because it suggests that early planets could form from dramatically different materials than those that produced Earth and Mars. It provides a window into a lost pathway of planetary evolution, where a massive world existed, was shattered into rubble by a violent collision, and left only a few fragments to eventually land on Earth.
Opens the Intellect+ feed with this card first. Swipe up for the next one.
Sources
- Summary by Intellect · source: Strong Evidence for a Previously Unknown Destroyed Planet in the Solar System
- Also: Meteorite reveals a lost moon-sized world from the dawn of the solar system
- Also: Rare meteorite provides evidence of giant early planet
To cite this card, link to https://intellectplus.co.uk/app/space-strong-evidence-for-a-previously-unknown-destroyed-planet-in.
How we source, check and correct cards: Editorial standards.
General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.
Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?
Related
More in Astronomy · More in Space · Latest · A–Z · All topics
