Ancient Meteorite Grains Saved a Magnetic Clue
Tiny grains from an ancient meteorite preserved clues about a powerful magnetic field from the Solar System’s earliest days.
9/17/2026Scientists found a kind of fossil of a magnetic field in microscopic grains from one of the oldest known meteorites. The field existed during the first 200,000 years of the Solar System’s history.
The studied calcium-aluminum inclusions formed about 4.6 billion years ago. Their minerals kept a record of the magnetic field around them, which measurements suggest was about 150–600 microteslas—roughly 3–12 times stronger than Earth’s modern magnetic field.
The discovery suggests that gravity was not the only force shaping the young Sun. A magnetic field may have helped move gas and dust through a spinning disk of matter toward its center, helping the young Sun collect mass. These tiny meteorite pieces preserved this record for more than 4.5 billion years, from before the Solar System looked like it does today.