Archaeologists Devise a Better Clock for Biblical Times

Curiously, other data indicate that, about a century later, Hazael’s soldiers set fire to several settlements: Tel Rehov, Tel Zayit and Horvat Tevet, in addition to Gath, one of the five royal cities of the Philistines (and home to Goliath), whose destruction is noted in 2 Kings 12:17. The study, which examined the geomagnetic records at all four sites at the time of demolition, strongly suggests that they were burned during the same military offensive, according to the researchers.

Mr. Vaknin spent four years pioneering the application of paleomagnetic research to biblical archaeology, aided by his doctoral advisers, Dr. Lipschits, Erez Ben-Yosef of Tel Aviv University and Ron Shaar of the Institute of Earth Sciences at the Hebrew University of Jerusalem.

Besides helping to date archaeological contexts, the technology provides invaluable information on Earth’s magnetic field, one of the most enigmatic phenomena in geoscience. “Since instrumental recording of the field started about 200 years ago, the field’s strength has declined, and there is a danger that we might lose it completely,” Dr. Ben-Yosef said. “Understanding this trend and how dangerous it is requires data on the past behavior of the field.”

Earth’s magnetosphere is a protective bubble that deflects solar winds, streams of charged particles from the sun that gust through the solar system, and cosmic rays from deep space. Scientists theorize that the magnetic field is generated by a layer of molten iron and nickel in the planet’s outer core, about 1,800 miles below the surface, that is in continual flux around a solid iron core. As ferromagnetic particles in ancient artifacts cool, their magnetic moments are baked into the alignment. So long as the objects don’t heat up again, they will retain what is effectively a fossilized magnetic field. Each reheating beyond a certain temperature wipes out all previously recorded magnetic signals, so that the date is always of the most recent firing.

From around 800 to 400 B.C., as a result of changes in the percentage of radiocarbon in the atmosphere, the resolution of radiocarbon dating during those years is so limited that archaeologists seldom use it.

Dr. Ben-Yosef said he hoped that the new dating method would finally settle questions about the fall of the Kingdom of Judah. While it is widely accepted that the Babylonians laid waste to the Judean polity in 586 B.C., some researchers, relying on historical and archaeological evidence, argue that the invaders were not solely responsible. The intensity of the magnetic field as recorded in the destruction layer of the site of Malhata — a city on the southern periphery of Judah — is different and significantly lower than the one recorded in the Babylonian destruction of Jerusalem, the capital of the kingdom.” This means that the two destructions cannot be related to the same event,” Dr. Ben-Yosef said.

The archaeomagnetic data provided clear evidence that Malhata was destroyed decades later, a scenario that fits the notion that the Edomites, Judah’s southern neighbors, took advantage of the weakness of the Judahites after the Babylonian attack, decimated their southern cities and raided their territory.