(Israel Antiquities Authority/Shai Halevi)

Scientists used recorded data to link the Holy Temple’s destruction on a specific date in 586 BCE to measurements of the earth’s magnetic field on that day.

By Yakir Benzion, United With Israel

In an amazing piece of scientific work, researchers in Jerusalem were able to measure what the magnetic field of the planet Earth was exactly 2586 years ago.

It’s a combination of the Jewish commemoration of the 9th of the Hebrew month of Av (Tisha B’Av) with the phenomenon known as archaeomagnetic dating – the ability to measure what the direction and magnitude of the earth’s magnetic field was in ancient times when magnetic material that was in a fire is cooled – “freezing” the magnetic information in place.

It is indeed a fascinating connection. Albert Einstein defined fluctuations in the earth’s magnetic field as one of the five great mysteries of physics. That field surrounds the earth and protects life on the planet from invisible but deadly radiation from outer space. It is also used as a navigation tool by humans, birds and marine mammals.

But the earth’s magnetic field is not totally understood. It changes, and the north and south poles are known to flip locations periodically.

Archaeologists enter the picture because of archaeomagnetic dating, and what they unearth at digs helps geologists understand the what the magnetic field was in the past.

When magnetic minerals are heated, like in a fire or a volcano, and then cooled, the magnetic orientation is ‘frozen’ and can give a permanent record of the earth’s magnetic field at that moment. This is also true of archaeological findings such as pottery sherds, bricks, roof tiles and furnaces that ‘recorded’ the magnetic field as they cooled after being burned.

Thus, Jews know that the destruction of the Temple took place on the 9th of Av in 586 BCE, and recent excavations at City of David in Jerusalem allowed scientists to measure Earth’s magnetic field on that day – revealing as well the immensity of the destruction of Jerusalem by the Babylonians.

“We dated the destruction of the structure to 586 BCE — the destruction of Jerusalem by the Babylonians, based on smashed pottery vessels typical of the end of the First Temple period,” said Dr. Yiftah Shalev of the Israel Antiquities Authority.

“We found signs of burning and large quantities of ashes. The findings are reminiscent of the 2nd Book of Kings chapter 25 verse 9: “And he burnt the house of the Lord, and the king’s house, and all the houses of Jerusalem, and every great man’s house burnt he with fire.”

By measuring the magnetic field recorded in a fragment of pottery, the researchers were able to reveal earth’s magnetic field at the time of the fire.

PhD student Yoav Vaknin said they managed to rediscover the direction and magnitude of the magnetic field on the day of Jerusalem’s destruction. Also, the fire that destroyed the city in different places showed a link between the destruction of Jerusalem and the earth’s magnetic field –  thereby contributing to both geophysical and archaeological research.

“Measuring magnetic data from a floor burned thousands of years ago is no trivial matter,” said Dr. Ron Shaar of the Institute of Earth Sciences at the Hebrew University. “Nature hasn’t made life easy for us.”

“We very rarely have a historical event that occurred thousands of years ago that we can date so accurately — down to the year, month and even day, like the destruction of Jerusalem,” Vaknin said.

“It’s important to understand that … the description of the events that occurred in the Kingdom of Judea during its last 100 years was written almost in real time — and the Biblical text is generally considered reliable for this period.”