🧲 This meteorite preserved an imprint of the Sun’s formation

A meteorite that fell in Antarctica preserved an imprint more than 4.5 billion years old, dating back to the very first moments of the Solar System.

At that time, the Sun and planets had not yet taken their present form. Our neighborhood consisted of a cloud of gas and dust that gradually flattened into a disk. The material in this disk then fed the young Sun and supplied the materials from which the planets formed.

Researchers studied DOM 08006, a meteorite discovered in 2008 in the Dominion Range of Antarctica. It has remained particularly well preserved since its formation. In tiny fragments, the team isolated grains that appeared during the first 200,000 years of the Solar System. These calcium- and aluminum-rich grains are among the oldest known materials in our cosmic neighborhood.

Some of these grains contain iron-bearing minerals. When they formed, these tiny elements may have recorded the magnetic field present around them. Their residual magnetization therefore acts as a physical memory, still measurable after several billion years.

The measurements indicate a field of about 150 to 600 microteslas. To give a sense of scale, this corresponds to roughly three to twelve times the strength of Earth’s current magnetic field. This imprint dates back to a period far earlier than previous measurements obtained from meteorites, which concerned a Solar System already about two million years old.

To understand its importance, we need to look at how matter fell toward the young Sun. Gravity naturally drew gas and dust toward the center. But electrically charged matter could also interact with a magnetic field. These interactions facilitate the movement of gas within the disk and may therefore help feed the nascent star.

In other words, gravity may not have worked alone. The intensity found in the grains is consistent with models in which magnetism plays an important role in transporting matter toward the Sun.

This discovery therefore pushes the material evidence for a magnetic field in our Solar System much farther back in time. Researchers now have a direct measurement with which to test models describing the transition from the initial cloud to the disk surrounding the young Sun.

Other primitive meteorites may preserve comparable records. Analyzing them would help determine how the field’s intensity varied with distance from the Sun and over time, allowing scientists to better reconstruct the first few hundred thousand years of our planetary system.