They found a 45-meter wide, 16-meter deep impact crater filled with sand in southwestern Egypt.
The researchers think the rock that came crashing to Earth had a mass of between 5 and 10 metric tons (approximately 11,023 and 22,046 pounds) when it impacted the ground at a speed of about 3.5 kilometers (around 2.1 miles) per second.
The size and speed of the rock would have caused it to vaporize as soon as it hit the ground.
It you had been standing on that same spot at the time of impact, you, too, would have been vaporized.
The scientists estimate that the iron-based meteorite slammed into the Earth around five thousand years ago, plus or minus a couple of thousand years.
Page two continues.
The article is entitled 'The Kamil Crater in Egypt' and was authored by Dr. Luigi Folco, along with seventeen other colleagues from Italy and Egypt,
They state in the abstract of the paper: "We report on the detection in southern Egypt of an impact crater 45 meters in diameter with a pristine rayed structure. Such pristine structures are typically observed on atmosphereless rocky or icy planetary bodies in the solar system.'
And, 'This feature and the association with an iron meteorite impactor and shock metamorphism provide a unique picture of small-scale hypervelocity impacts on the Earth's crust. Contrary to current geophysical models, ground data indicate that iron meteorites with masses of the order of tens of tons can penetrate the atmosphere without significant fragmentation."
The rim of the Kamil Crater is about 3 meters higher than the surrounding plain. More importantly, the researchers saw light-colored material coming out of the center of the crater, much like the spokes of a wagon wheel.
Page three concludes with the reason for their special interest in sand-colored spoke-like patterns.
On Earth, its atmosphere usually erases such spokes quite quickly. The researchers concluded that the impact crater hasn't been there very long.
To learn more about why the Kamil Crater is important to the frequency of meteorites hitting the Earth, please read the July 22, 2010 National Geographic News article "'Fresh' Crater Found in Egypt; Changes Impact Risk?.'
The article raises the possibility for frequent collisions with Earth: It states, 'There are no hard numbers for how many meteors this size might currently be on a collision course with Earth, but scientists think the potential threats could be in the tens of thousands.'
And, 'Current impact models state that iron meteors around this size and mass should break into smaller chunks before impact.'
However, 'Instead, the existence of the newfound crater implies that up to 35 percent of these iron giants may actually survive whole'”and thus have greater destructive power.'
Please read the National Geographic article for more details.