Ancient bricks baked when Nebuchadnezzar II was king absorbed a power surge in Earth’s magnetic field

CNN: Thousands of years ago, Earth’s magnetic field underwent a significant power surge over a part of the planet that included the ancient kingdom of Mesopotamia. People at the time probably never even noticed the fluctuation, but signs of the anomaly, including previously unknown details, were preserved in the mud bricks that they baked, new research has found.

When scientists recently examined bricks dating from the third to the first millennia BC in Mesopotamia — which encompassed present-day Iraq and parts of what is now Syria, Iran and Turkey — they detected magnetic signatures in those from the first millennium, indicating that the bricks were fired at a time when Earth’s magnetic field was unusually strong. Stamps on the bricks naming Mesopotamian kings enabled researchers to confirm the time range for the magnetic spike.

Their findings corresponded with a known magnetic surge called the “Levantine Iron Age geomagnetic Anomaly,” which took place between 1050 and 550 BC. It had previously been documented in artifacts from the Azores, Bulgaria and China using archaeomagnetic analysis — examining grains in pottery and ceramic archaeological objects for clues about Earth’s magnetic activity, scientists reported December 18 in the journal Proceedings of the National Academy of Sciences.

“It is really exciting that ancient artifacts from Mesopotamia help to explain and record key events in Earth history such as fluctuations in the magnetic field,” said study coauthor Mark Altaweel, a professor of Near East archaeology and archaeological data science at the University College London’s Institute of Archaeology.

“It shows why preserving Mesopotamia’s ancient heritage is important for science and humanity more broadly,” Altaweel told CNN in an email.