The Earth's magnetic field tells the story of the destruction of the First Temple

A joint interdisciplinary study by the Hebrew University, Tel Aviv University and the Antiquities Authority in the City of David in the National Park surrounding the walls of Jerusalem for the first time, researchers were able to reconstruct the Earth's magnetic field with the precision of a single day: Tisha B'av 586 BC and reveal the intensity of the destruction of Jerusalem at the hands of the Babylonians . The reconstruction of the magnetic field in the destruction of Jerusalem will be an exceptional chronological anchor for archaeomagnetic dating - up to a level of accuracy of a single day. The magnetic measurements proved that when the first house was destroyed, the building burned, probably intentionally, and that the floor of its upper floor, which rested on massive wooden beams, collapsed during the fire. The study is published near Tisha B'av in the journal PLOS ONE

Every year on Tisha B'Av, Jews around the world remember the destruction of the First Temple. Now, thanks to the long historical memory of the Jewish people, and thanks to archaeological findings recently uncovered in the excavations of the City of David, researchers from Tel Aviv University, the Hebrew University and the Antiquities Authority have succeeded in reconstructing the magnetic field of the earth in August 586 BC - and revealing the power of the destruction of Jerusalem at the hands of the Babylonians.

The interdisciplinary and groundbreaking research, published near Tisha B'av in the journal PLOS ONE, is based on the doctoral thesis of Yoav Vakanin from the Department of Archeology at Tel Aviv University, in collaboration with researchers Dr. Ron Shaar from the Hebrew University of Jerusalem, Prof. Erez Ben Yosef, Prof. Oded Lifshitz and Prof. Yuval Gadot from the Department of Archeology at Tel Aviv University, and Dr. Yeftah Shalu from the Antiquities Authority.

The variation of the Earth's magnetic field was defined by Albert Einstein as one of the five great mysteries in physics. Although the magnetic field that surrounds the Earth is invisible, it plays an important role in the life of the planet. It is the protective screen against radiation from space that enables the existence of life on Earth, and is a navigational tool for humans, birds and marine mammals. Despite its importance, we know very little about the magnetic field - how exactly does the mechanism that produces it in the earth's core work? How and why does the field change? And how do the changes in the magnetic field affect the Earth's atmosphere?

To answer these questions and explain its enigmatic behavior, geophysicists try to trace the behavior of the magnetic field before starting the measurements. For this purpose, you can use archeological findings - such as pottery, bricks, roof tiles and kilns - that "recorded" the magnetic field while they were being burned. These findings contain magnetic minerals that were remagnetized according to the direction and strength of the field at the same time - and are a window into the history of the magnetic field. The destruction of Jerusalem, dated to the year 586 BC, can be used as an exceptional chronological anchor for archaeomagnetic dating - up to a level of accuracy of a single day.

During an excavation that is currently underway in the city of David in the Sobb National Park surrounding the walls of Jerusalem, in the place where the "Givati ​​parking lot" used to be, the researchers discovered a magnificent public building with a high-quality plaster floor. The managers of the excavation, Dr. Yeftah Shalu from the Antiquities Authority and Prof. Yuval Gadot from Tel Aviv University, explain: "We dated the destruction of the building to 586 BC, the destruction of Jerusalem by the Babylonians, based on pottery typical of the end of the First Temple period, which were found on the floor when they are smashed. Besides the broken pottery, signs of fire and a lot of ash were also discovered. These findings remind us of what is written in the Book of Kings: "And he burned the house of God and the house of the king and all the houses of Jerusalem and every great house he burned with fire" (XNUMX Kings, XNUMX, verse XNUMX). In the same "big house" that burned, the researchers uncovered a large fragment of a floor that had collapsed from the top floor of the building - and by studying the magnetic field recorded in it, they reconstructed the Earth's magnetic field at the time of the fire.

Doctoral student Yoav Vakanin from Tel Aviv University collected the fragments of the floor, which were scattered in different directions on the site, and measured the magnetic field recorded in them in the paleomagnetic laboratory at the Institute of Earth Sciences of the Hebrew University. "The purpose of the research was twofold," says Vaknin. "On the one hand, the goal was to reconstruct the direction and strength of the magnetic field on the day of the Holocaust, and on the other hand, we wanted to understand what the magnetic information embedded in the fragments of the floor could tell us about the Holocaust itself. Even without the measurement of the magnetic field, it could be assumed that this magnificent building was destroyed in the destruction of the First Temple, but the magnetic measurements proved that the building burned at a temperature of more than 500 degrees Celsius, probably intentionally, and that the floor, which rested on massive wooden beams, collapsed during the fire.

We could reach this conclusion based on the fact that most of the floor blocks, which cooled after the collapse, recorded a uniform direction regardless of the position they fell into. We were able to link the destruction of the house to the Earth's magnetic field, thus contributing to both the Earth's geophysical research and archaeological research. It's really unusual. The archaeomagnetic method also has implications for further research. If tomorrow we find a ruin layer with similar ceramics at another ruin site, we will be able to compare the magnetic field recorded in it and thus help determine if it was also destroyed by the Babylonians."

Dr. Ron Shaar from the Institute of Earth Sciences at the Hebrew University: "Measuring magnetic information from a floor that burned thousands of years ago is not a trivial matter. The magnetic particles must be characterized, understand how the magnetic information is encoded in the material and develop measurement methods that allow us to read this information. Nature does not make life easy for us. Therefore, a significant part of the analytical work we do in the paleomagnetic laboratory is to investigate in depth the magnetic properties of the archaeological material. Fortunately, in this research Yoav was able to crack nature's magnetic coding and provide us with important information from several angles - historical, archaeological and geomagnetic."

Vakanin concludes: "In order to reconstruct the magnetic field, you need sources of information from well-established historical points. Very rarely do we have a historical event from thousands of years ago that we know how to date at the level of the year, the month and even today such as the destruction of the First Temple. It should be understood that although there are debates about the historical validity of the Bible as a whole, the description of the events that took place in the kingdom of Judah in the last hundred years of its existence were written almost in real time - and the biblical text is generally considered reliable regarding this period. The destruction of the First Temple is supported by a number of archaeological findings from the Land of Israel in general and Jerusalem in particular, such as jars with seal impressions of the Varda type, belonging to the Kingdom of Judah, and seal impressions with names mentioned in the Bible.

for the scientific article

More of the topic in Hayadan:

• The priesthood as you did not know it - part XNUMX: the end of the days of the First Temple and the exile in Babylon
• An administrative center from the period of the Kingdom of Judah was discovered in excavations in southern Jerusalem
• Pepper dates * Were the two temples destroyed on Tisha B'Av?
• Scientists: The weakening of the Earth's magnetic field is not a new phenomenon