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http://www.esa.int : Egyptian desert expedition confirms spectacular meteorite impact
...23 September 2010
Expedition leader Mario Di Martino at Kamil crater
A 2008 Google Earth search led to the discovery of Kamil crater, one of the best-preserved meteorite impact sites ever found. Earlier this year, a gritty, sand-blown expedition reached the site deep in the Egyptian desert to collect iron debris and determine the crater's age and origins.
One day within the last several thousand years, a rare metallic meteorite travelling over 12 000 km/hour smashed into Earth's surface near what is today the trackless border region between Egypt, Sudan and Libya. The impact of the 1.3 m, 10-tonne chunk of iron generated a fireball and plume that would have been visible over 1000 km away, and drilled a hole 16 m deep and 45 m wide into the rocky terrain.
Since then, the crater had sat undisturbed by Earth's geologic and climatic processes, which usually render all but the very largest terrestrial impact craters invisible. It was also, as far as is recorded, unseen by humans.
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After a tiring, GPS-guided, three-day drive across the desert in 40°C heat, the team reached the crater.
Three-day drive to reach Kamil crater
They collected over 1000 kg of metallic meteorite fragments, including one 83-kg chunk thought to have split from the main meteorite body shortly before impact (it was found 200 m away from the crater). The joint team also conducted a thorough geological and topographical survey, using ground-penetrating radar to create a 3D digital terrain model. Geomagnetic and seismic surveys were also carried out.
...The researchers were stunned to find that Kamil crater, named after a nearby rocky outcrop, remains pristine, and must have been created relatively recently.
"This demonstrates that metallic meteorites having a mass on the order of 10 tonnes do not break up in the atmosphere, and instead explode when they reach the ground and produce a crater," says ESA's Dr Detlef Koschny, Head of Near Earth Objects segment for the SSA programme.
..The intriguing story of the Kamil crater discovery will be presented in a joint paper by Telespazio, e-Geos, ASI and INAF, 'Radar observation of impact craters using COSMOSkyMed' at the European Planetary Science Congress (EPSC) 19-25 September 2010, in Rome. A public and media outreach event, 'Kamil: a Lunar Crater on Earth', will be presented on 23 September at the University of Rome (more information here).