“The magnetic field is invisible, but it plays a critical role in the life of our planet. Without the geomagnetic field, nothing on Earth would be as it is — maybe life wouldn’t have evolved without it,” told Prof. Ron Shaar of Hebrew University to The Times of Israel. This silent power, forged deep in the Earth’s core, has proved an unexpected partner in deciphering the blazing ruin of lost cities and, with them, the very events documented in the Hebrew Bible.
Over the last ten years, archaeomagnetism a discipline previously confined to the fringes of archaeological dating has come into its own as a high-precision tool, enabling scientists to align the dates of biblical conquests with the planet’s own magnetic record. The technique is as beautiful as it is powerful: when ancient cities were burned, the high temperatures rearranged magnetic minerals in ceramics and mud bricks, imprinting an archive of the Earth’s magnetic field at the time. These materials, unearthed centuries later, serve as time capsules, their “magnetic fingerprints” as distinct as the events that shaped them.
An interdisciplinary team from Hebrew University of Jerusalem and Tel Aviv University recently analyzed 21 layers of destruction from 17 sites throughout Israel, using both radiocarbon and archaeomagnetic information to generate a high-resolution conflict and collapse timeline. The consequences are deep-reaching, not just for biblical archaeology, but for the dynamics of the Earth’s core as well. As doctoral student Yoav Vaknin described in a press statement, “Based on the similarity or difference in intensity and direction of the magnetic field, we can either corroborate or disprove hypotheses claiming that specific sites were burned during the same military campaign.” The technique, he said, is similar to radiocarbon dating but “based on magnetic field variations.”
One of the most compelling synchronizations is from the campaign of King Hazael of Aram-Damascus. The destruction of Gath, Tel Rehov, Tel Zayit, and Horvat Tevet was for centuries ascribed to different causes for decades. However, the new research discovered that all four sites have the same magnetic signatures, establishing their destruction in one campaign around 830 BCE a rare convergence of archaeological, textual, and geophysical evidence. This observation is confirmed by Gath’s excavator, Prof. Aren Maeir, who told The Times of Israel, “We got perfect agreement between four sites in intensity, and in most of them we also have direction results.”
The case of Tel Beth-Shean shows the force of this method to disrupt established narratives. Long believed to have fallen into the hands of Hazael, the site’s magnetic fingerprint actually corresponds to an earlier date, with the military campaign of Pharaoh Shoshenq I, the biblical Shishak. This new dating, confirmed by both Egyptian inscriptions and biblical accounts, reorders the chronology of local power struggles and shows how archaeomagnetism can settle arguments that have gone on for decades. As detailed in the Armstrong Institute’s coverage, “the magnetic field squares with material associated with Sheshonq/Shishak’s invasion in the 10th century b.c.e. (But perhaps this is not overly surprising, as Sheshonq’s defeat of Beth-Shean is listed on his victory wall inscription in the Temple of Amun at Karnak.)” the magnetic field squares with material associated with Sheshonq/Shishak’s invasion in the 10th century b.c.e. (But perhaps this is not overly surprising, as Sheshonq’s defeat of Beth-Shean is listed on his victory wall inscription in the Temple of Amun at Karnak.)
The precision of the method is especially useful in the so-called Hallstatt Plateau (ca. 800–400 BCE), a time when radiocarbon dating is problematic due to the difficulties of calibration. The gap is filled by archaeomagnetic data anchored to well-dated events like the 586 BCE destruction of Jerusalem by the Babylonians. As the Vaknin paper points out, “This is especially useful during the Hallstatt Plateau (ca. 800–400 BCE), a period in which the resolution of radiocarbon dating is limited.” This is particularly convenient during the Hallstatt Plateau (ca. 800–400 BCE), an era in which the resolution of radiocarbon chronology is low.
Archaeomagnetic and radiocarbon dating integrated together are not a matter of preference but a necessity from a scientific standpoint. Radiocarbon dating, although useful, can be problematic because of atmospheric variation in carbon-14 and statistical error, particularly when employing summed probability densities. Recent developments in Bayesian statistical modeling have started to overcome these challenges, allowing researchers to integrate archaeological context with radiocarbon data for more precise reconstructions. As SFI Fellow Michael Price noted, “The approach also allows them to combine additional archaeological information with radiocarbon analyses to get a more accurate population estimate.” The method also enables them to add further archaeological data in with the radiocarbon analysis to achieve a more realistic population estimate.
In addition to its application in archaeology, the study has also produced surprising insights into the Earth’s magnetic field itself. The densely occupied archaeologically Southern Levant now serves as a natural laboratory for paleomagnetic research. Throughout the times in question, the area witnessed fast, high-strength geomagnetic spikes at some points more than twice the strength of the field today. Prof. Ron Shaar stressed, “Our results show that the magnetic field is far less stable than previously thought. This knowledge is vital for understanding Earth’s core dynamics and refining geophysical models.” These discoveries undermine the long-standing understanding of the geodynamo as a steady, slow process, instead showing the system to be one that can suddenly and spectacularly change.
The geodynamo, powered by turbulent molten iron and nickel flows almost 3,000 kilometers under our feet, generates the magnetic field that protects life from cosmic radiation. As explained in Physics Today, “In such a dynamo, electric currents and magnetic fields are continuously induced by motions of conducting fluid inside the planet.” The new paleomagnetic records from Israel and Jordan are now being inputted into global models, tuning our knowledge of how the field has cycled up and down over millennia.
This multi-disciplinary approach blending archaeology, biblical history, and geophysics has also pushed the Levantine Archaeomagnetic Curve back to the Neolithic, thanks to work on burnt pottery and even flint tools at sites in Jordan. As Scripps geophysicist Lisa Tauxe pointed out, “Our results suggest that one of the weakest magnetic fields of the last 10,000 years in the Levant occurred around 7,600 BCE, when it was about half of today’s magnetic field.” Our results indicate that one of the lowest magnetic fields of the past 10,000 years in the Levant was around 7,600 BCE, when it was roughly half of the current magnetic field.
As scorched ruins’ magnetic memory remains to be deciphered, the partnership between earth scientists and archaeologists is rewriting not just our understanding of past events, but also the dynamic processes that shape our planet’s interior. The magnetic imprints stored in the wake of ancient conflicts now lead both the reconstruction of biblical history and the development of the geodynamo models explaining how Earth’s magnetic shield persists and waxes and wanes over time.
