Scientists at the Massachusetts Institute of Technology have identified records of ancient magnetism in microscopic mineral grains from an Antarctic meteorite, MIT reported. The measurements suggest a magnetic field existed during the solar system's first 200,000 years and helped draw primordial gas and dust inward to form the sun.
Researchers analyzed calcium-aluminum-rich inclusions, or CAIs, embedded in a primitive meteorite designated DOM 08006. Field teams recovered the sample in 2008 from the Dominion Range along the East Antarctic Ice Sheet. CAIs represent the oldest known solid material from the solar system, dating to its earliest nebular stage roughly 4.6 billion years ago.
Magnetic Measurements
Tests on isolated grains containing magnetic minerals such as iron revealed remnant magnetization ranging between 150 and 600 microteslas. That field strength is three to 12 times greater than Earth's current magnetic field. The team published the findings in the Proceedings of the National Academy of Sciences under DOI 10.1073/pnas.2521660123.
Scientists previously relied on gravity to explain how the collapsing solar nebula flattened from a spherical gas cloud into a protoplanetary disk. Moving charged particles in the collapsing cloud generated a plasma that sustained magnetic fields across the disk. These fields then transferred momentum and channeled gas toward the central protostar.
First author Cauê Borlina, an assistant professor at Purdue University who led the project while at MIT, conducted the study with Robert R. Shrock Professor of Earth and Planetary Sciences Benjamin Weiss. Co-authors included Elias Mansbach and Nilanjan Chatterjee of MIT, Xue-Ning Bai of Tsinghua University, Po-Yen Tung and Richard Harrison of Cambridge University, François Tissot of Caltech, and Kevin McKeegan of UCLA. NASA provided partial funding support for the research.
