The most accurate laboratory measurements yet made of magnetic fields trapped in grains within a primitive meteorite are providing important clues to how the early solar system evolved. Scientists studied magnetic fields inside these primitive meteorite chunks, which provided evidence of “shock waves” that traveled from the early sun through the dusty gas cloud of the early solar system that was the key to its formation, according to Astronomy Magazine.
The solar system’s formation was a messy process 4.5 billion years ago that left lots of rocky material that act as a time capsule for the solar system.
Among the most useful pieces of debris are the oldest, most primitive and least altered type of meteorites, called the chondrites. Chondrite meteorites are pieces of asteroids, broken off by collisions, that have remained relatively unmodified since they formed at the birth of the solar system. They are built mostly of small stony grains, called chondrules, barely a millimeter in diameter.
Chondrules themselves formed through quick melting events in the dusty gas cloud, the solar nebula, which surrounded the young sun. As chondrules cooled, iron-bearing minerals within them became magnetized like bits on a hard drive by the local magnetic field in the gas. These magnetic fields are preserved in the chondrules even down to the present day.
The chondrule grains whose magnetic fields were mapped in the new study came from a meteorite named Semarkona, after the place in India where it fell in 1940. It weighed 691 grams, or about a pound and a half.
What these tiny magnetic fields showed is that shockwaves passed through solar nebula and amplified the background magnetic field by up to 30 times, which suggests that shock waves melted rock as far away as today’s asteroid belt, which is two to four times farther from the sun than earth.