Earth’s geomagnetic field has been fluctuating for thousands of years but not disappearing, according to a new study conducted by researchers from Tel Aviv University, Hebrew University of Jerusalem and University of California-San Diego.
New evidence – in form of changes in the strength of the geomagnetic field – was found in 67 well-dated Judean jar handles, heat-impacted ceramic pots, which bear royal stamp impressions from the eighth to second centuries BC.
To accurately measure geomagnetic intensity, the researchers used laboratory-built paleomagnetic ovens and a superconducting magnetometer.
The function of the geomagnetic field is still not completely understood but according to Ben-Yosef, the phenomenon is not unique and the field has often weakened and recovered over the last millennia.
Study is published in Proceedings of the National Academy of Sciences (PNAS).