As the residents of an ancient Middle Eastern city now called Tall al-Hammam went about their daily business one day some 3,600 years ago, they didn’t know that an undiscovered icy space rock could travel about 38,000 miles per day. was moving towards them at a speed of 61,000 kilometers per hour.
Glowing into the atmosphere, the rock erupted into a giant fireball about 2.5 miles (4 kilometers) above the ground. The explosion was about 1,000 times more powerful than the Hiroshima atomic bomb. The shocked townspeople who saw this immediately went blind. The air temperature quickly rose above 3,600 degrees Fahrenheit (2,000 degrees Celsius). Clothes and wood immediately engulfed in flames. Swords, spears, clay bricks and pottery began to melt. Almost immediately, the whole city was on fire.
A few seconds later, a massive tremor blew the city. Moving at about 740 mph (1,200 kph), it was more powerful than the worst tornado ever recorded. Deadly winds knocked on the city, demolishing every building. He cut off the top 40 feet (12 m) of the 4-story palace and blew the rubble into the next valley. None of the 8,000 people or any animals within the city survived – their bodies were torn apart and their bones broken into small pieces.
About a minute later, 14 miles (22 km) west of Tal al-Hammam, winds from the eruption moved to the biblical city of Jericho. The wall of Jericho collapsed and the city was reduced to ashes.
It all feels like the climax of a Hollywood disaster movie on the edge of your seat. How do we know that all this actually happened thousands of years ago near the Dead Sea in Jordan?
NASA, CC BY-ND
Nearly 15 years of painstaking excavations were required by hundreds of people to get the answer. It also included a detailed analysis of the excavated material by more than two dozen scientists in 10 states in the US as well as Canada and the Czech Republic. When our group recently published the evidence in the journal Scientific Reports, 21 co-authors included archaeologists, geologists, geochemists, geomorphologists, mineralogists, paleobotanists, sedimentologists, cosmic-impact specialists and medical doctors. Were.
Here’s how we created this picture of devastation in the past.
thunderstorm across the city
Years ago, when archaeologists looked at the excavations of the ruined city, they saw a nearly 5-foot-thick (1.5 m) frozen layer of charcoal, ash, molten clay bricks and molten pottery. It was clear that a long time ago a fierce firestorm had devastated the city. This dark band came to be called the destruction layer.
Phil Sylvia, CC BY-ND
No one was quite sure what had happened, but that crust was not caused by volcanoes, earthquakes, or war. None of these is capable of melting metals, clay bricks and pottery.
To find out what might have happened, our group used an online impact calculator to model scenarios that are consistent with the evidence. Created by impact experts, this calculator allows researchers to estimate many details of a cosmic impact event based on known impact events and nuclear explosions.
It appears that the culprit of Tall el-Hammam was a small asteroid that downed 80 million trees in Tunguska, Russia, in 1908. It would have been a much smaller version of the giant mile-wide rock that pushed the dinosaurs apart. In extinction 65 million ago.
We had a possible culprit. Now we needed proof of what happened in Tal al-Hammam that day.
Finding ‘Diamonds’ in the Dirt
Our research revealed a remarkably wide range of evidence.
allen west, CC BY-ND
At the site, there are grains of finely fractured sand called Shocked Quartz that form at just 725,000 pounds per square inch of pressure (5 gigapascals)—imagine six 68-ton Abrams military tanks piled on your thumb.
The destruction layer also contains small diamonds that, as the name indicates, are as hard as diamonds. Each is smaller than a flu virus. It appears that the wood and plants in the area were instantly turned into this diamond-like material by the high pressure and temperature of the fireball.
Malcolm Lecompte, CC BY-ND
Experiments with laboratory furnaces showed that the bubbling pottery and clay bricks at Tal al-Hammam were liquefied at temperatures above 2,700 F (1,500 C). It gets so hot that it melts an automobile in minutes.
Malcolm Lecompte, CC BY-ND
The destruction layer also contains tiny balls of molten material that are smaller than dust particles blown in the wind. Called spheroids, they are made of vaporized iron and sand that melt at about 2,900 F (1,590 C).
In addition, the surfaces of pottery and meltglass are speckled with tiny molten metal grains, including iridium with a melting point of 4,435 F (2,466 C), platinum melting at 3,215 F (1,768 C), and 2,800 F. Contains zirconium silicate at F (1,540). C).
Together, all of this evidence suggests that temperatures in the city rose higher than volcanoes, wars, and normal city fires. The only natural process left which is a cosmic effect.
Similar evidence is found at known impact sites, such as Tunguska and Chicxulub craters, created by the asteroid that triggered the extinction of the dinosaurs.
A remaining puzzle is why the city and more than 100 area settlements were abandoned for several centuries after this devastation. It may be that the high levels of salt deposited during the impact event made it impossible to grow crops. We’re not sure yet, but we think the eruption may have vaporized or sprayed toxic levels of Dead Sea saltwater into the valley. Without crops, no one could live in the valley for 600 years, until at least in this desert-like climate, the salt ran out of the fields.
Were there any living eyewitnesses to the explosion?
It is possible that an oral account of the city’s destruction was passed down for generations, until it was recorded as the biblical story of Sodom. The Bible describes the devastation of an urban center near the Dead Sea – stones and fire fell from the sky, more than one city was destroyed, the fire raised thick smoke and the inhabitants of the city were killed.
Could it be an ancient eyewitness? If so, the destruction of Taal al-Hammam by a cosmic impact event may be the second oldest destruction of human settlement, after the village of Abu Hureyra in Syria, about 12,800 years ago. Importantly, this may be the first written record of such a horrific event.
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The scary thing is that it almost certainly won’t be the last time a human city meets this fate.
Tunguska-sized airbursts, such as those at Tal al-Hammam, can devastate entire cities and regions, and they pose a serious modern threat. As of September 2021, there are more than 26,000 known near-Earth asteroids and a hundred short-period near-Earth comets. One would inevitably crash into the earth. Millions more remain undetected, and some may now head to Earth.
Unless orbiting or on-ground telescopes detect these rogue objects, there may be no warning to the world, such as the people of Tall al-Hammam.
This article was co-authored by research associate archaeologist Phil Sylvia, geophysicist Alan West, geologist Ted Bunch and space physicist Malcolm Lecompte.
This article is republished from – The Conversation – Read the – original article.
