A giant space rock demolished an ancient Middle Eastern city and everyone in it – possibly inspiring the Biblical story of Sodom

Now called Tall el-Hammam, the city is located about 7 miles northeast of the Dead Sea in what is now Jordan. NASA, CC BY-ND^[2]

Getting answers required nearly 15 years of painstaking excavations by hundreds of people. It also involved detailed analyses of excavated material by more than two dozen scientists in 10 states in the U.S., as well as Canada and the Czech Republic. When our group finally published the evidence^[3] recently in the journal Scientific Reports, the 21 co-authors included archaeologists, geologists, geochemists, geomorphologists, mineralogists, paleobotanists, sedimentologists, cosmic-impact experts and medical doctors.

Here’s how we built up this picture^[4] of devastation in the past.

Firestorm throughout the city

Years ago, when archaeologists looked out over excavations of the ruined city, they could see a dark, roughly 5-foot-thick (1.5 m) jumbled layer of charcoal, ash, melted mudbricks and melted pottery. It was obvious that an intense firestorm had destroyed this city long ago. This dark band came to be called the destruction layer.

Researchers stand near the ruins of ancient walls, with the destruction layer about midway down each exposed wall. Phil Silvia, CC BY-ND^[5]

No one was exactly sure what had happened, but that layer wasn’t caused by a volcano, earthquake or warfare. None of them are capable of melting metal, mudbricks and pottery.

To figure out what could, our group used the Online Impact Calculator^[6] to model scenarios that fit the evidence. Built by impact experts, this calculator allows researchers to estimate the many details of a cosmic impact event, based on known impact events and nuclear detonations.

It appears that the culprit at Tall el-Hammam was a small asteroid similar to the one that knocked down 80 million trees^[7] in Tunguska, Russia in 1908^[8]. It would have been a much smaller version of the giant miles-wide rock that pushed the dinosaurs into extinction^[9] 65 million ago.

We had a likely culprit. Now we needed proof of what happened that day at Tall el-Hammam.

Finding ‘diamonds’ in the dirt

Our research revealed a remarkably broad array of evidence.

Electron microscope images of numerous small cracks in shocked quartz grains. Allen West, CC BY-ND^[10]

At the site, there are finely fractured sand grains called shocked quartz that only form at 725,000 pounds per square inch of pressure (5 gigapascals) – imagine six 68-ton Abrams military tanks^[11] stacked on your thumb.

The destruction layer also contains tiny diamonoids^[12] that, as the name indicates, are as hard as diamonds. Each one is smaller^[13] than a flu virus^[14]. It appears that wood and plants in the area were instantly turned into this diamond-like material by the fireball’s high pressures and temperatures.

Diamonoids (center) inside a crater were formed by the fireball’s high temperatures and pressures on wood and plants. Malcolm LeCompte, CC BY-ND^[15]

Experiments with laboratory furnaces showed that the bubbled pottery and mudbricks at Tall el-Hammam liquefied at temperatures above 2,700 F (1,500 C). That’s hot enough to melt an automobile^[16] within minutes.

Spherules made of melted sand (upper left), palace plaster (upper right) and melted metal (bottom two). Malcolm LeCompte, CC BY-ND^[17]

The destruction layer also contains tiny balls of melted material smaller than airborne dust particles. Called spherules^[18], they are made of vaporized iron and sand that melted at about 2,900 F (1,590 C).

In addition, the surfaces of the pottery and meltglass are speckled with tiny melted metallic grains, including iridium with a melting point of 4,435 F^[19] (2,466 C), platinum that melts at 3,215 F^[20] (1,768 C) and zirconium silicate at 2,800 F^[21] (1,540 C).

Together, all this evidence shows that temperatures in the city rose higher than those of volcanoes, warfare and normal city fires. The only natural process left is a cosmic impact.

The same evidence is found at known impact sites, such as Tunguska^[22] and the Chicxulub crater^[23], created by the asteroid that triggered the dinosaur extinction.

One remaining puzzle is why the city and over 100 other area settlements were abandoned for several centuries after this devastation. It may be that high levels of salt deposited during the impact event made it impossible to grow crops. We’re not certain yet, but we think the explosion may have vaporized or splashed toxic levels of Dead Sea salt water across the valley. Without crops, no one could live in the valley for up to 600 years, until the minimal rainfall in this desert-like climate washed the salt out of the fields.

Was there a surviving eyewitness to the blast?

It’s possible that an oral description of the city’s destruction may have been handed down for generations until it was recorded as the story of Biblical Sodom. The Bible describes the devastation of an urban center^[24] near the Dead Sea – stones and fire fell from the sky^[25], more than one city was destroyed, thick smoke rose from the fires and city inhabitants were killed.

Could this be an ancient eyewitness account? If so, the destruction of Tall el-Hammam may be the second-oldest destruction of a human settlement by a cosmic impact event, after the village of Abu Hureyra in Syria about 12,800 years ago^[26]. Importantly, it may the first written record of such a catastrophic event.

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The scary thing is, it almost certainly won’t be the last time a human city meets this fate.

Animation depicting the positions of known near-Earth objects at points in time for the 20 years ending in January 2018. Credit: NASA/JPL-Caltech

Tunguska-sized airbursts, such as the one that occurred at Tall el-Hammam, can devastate entire cities and regions, and they pose a severe modern-day hazard. As of September 2021, there are more than 26,000 known near-Earth asteroids^[28] and a hundred short-period near-Earth comets. One will inevitably crash into the Earth. Millions more remain undetected, and some may be headed toward the Earth now.

Unless orbiting or ground-based telescopes detect these rogue objects, the world may have no warning, just like the people of Tall el-Hammam.

This article was co-authored by research collaborators archaeologist Phil Silvia^[29], geophysicist Allen West^[30], geologist Ted Bunch^[31] and space physicist Malcolm LeCompte^[32].

Read more https://theconversation.com/a-giant-space-rock-demolished-an-ancient-middle-eastern-city-and-everyone-in-it-possibly-inspiring-the-biblical-story-of-sodom-167678

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