An MIT study suggests that a mysterious gap existed within the solar system’s protoplanetary disk around 4.567 billion years ago, and likely shaped the composition of the solar system’s planets.

A new analysis of ancient meteorites by scientists at MIT and elsewhere suggests that a mysterious gap existed within this disk around 4.567 billion years ago, near the location where the asteroid belt resides today.

Early planetary systems are governed by strong magnetic fields.

This physical separation could have shaped the composition of the solar system’s planets.

Scientists have proposed that this dichotomy may be the result of a gap in the early solar system’s disk, but such a gap has not been directly confirmed.

Weiss’ group analyzes meteorites for signs of ancient magnetic fields.

As a young planetary system takes shape, it carries with it a magnetic field, the strength and direction of which can change depending on various processes within the evolving disk.

As ancient dust gathered into grains known as chondrules, electrons within chondrules aligned with the magnetic field in which they formed.

Weiss’ group specializes in measuring chondrules to identify the ancient magnetic fields in which they originally formed.

Weiss’ group previously identified the ancient magnetic field in samples from this close-in region.

In their new study, the researchers wondered whether the magnetic field would be the same in the second isotopic, “carbonaceous” group of meteorites, which, judging from their isotopic composition, are thought to have originated farther out in the solar system.

Using the superconducting quantum interference device, or SQUID, a high-precision microscope in Weiss’ lab, the team determined each chondrule’s original, ancient magnetic field.

Surprisingly, they found that their field strength was stronger than that of the closer-in noncarbonaceous meteorites they previously measured.

As young planetary systems are taking shape, scientists expect that the strength of the magnetic field should decay with distance from the sun.

A planetary system’s magnetic field is a measure of its accretion rate, or the amount of gas and dust it can draw into its center over time.

Based on the carbonaceous chondrules’ magnetic field, the solar system’s outer region must have been accreting much more mass than the inner regionJ

October 13, 2021

October 13, 2021

October 13, 2021