From the European Space Agency via press release, the modern meteorite enthusiast’s dream – finding a crater on Google Earth and seeing it through to full discovery. As more and more hi-res images find their way in Google Earth, we will likely see more discoveries like this.
Egyptian desert expedition confirms spectacular meteorite impact
23 September 2010
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.
Searching for craters in Google Earth
But that changed in 2008, when the crater was spotted during a Google Earth study conducted by mineralologist Vincenzo De Michele, then with the Civico Museo di Storia Naturale in Milan, Italy. He was searching for natural features, when by chance he saw the rounded impact crater on his PC screen.
De Michele contacted an astrophysicist, Dr Mario Di Martino, at the INAF (National Institute for Astrophysics) observatory in Turin, who, together with Dr Luigi Folco, of Siena’s Museo Nazionale dell’Antartide, organised an expedition to the site in February this year.
It took over a year to plan and obtain permissions for the journey; in the meantime, and in collaboration with Telespazio, e-Geos and the Italian space agency ASI, the Kamil region was analysed using satellite data and in particular high-resolution radar images provided by the ASI-operated COSMO-SkyMed satellite constellation.
Expedition to the Egyptian desert
The two-week, 40-person expedition included Egyptian and Italian scientists, as well as numerous local support workers, and was conducted as part of the 2009 Italian-Egyptian Year of Science and Technology (EISY). It was also supported with funding by ESA’s Space Situational Awareness (SSA) programme.
After a tiring, GPS-guided, three-day drive across the desert in 40°C heat, the team reached the 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.
Ground truth for small-scale impact craters
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.
Kamil crater has become the target of intense interest for geologists, astrophysicists and even archaeologists.
“We are still determining the geochronology of the impact site, but the crater is certainly less than ten thousand years old — and potentially less than a few thousand. The impact may even have been observed by humans, and archaeological investigations at nearby ancient settlements may help fix the date,” says Dr Folco.
The data gathered during the expedition will be very useful to ESA’s SSA activities for risk assessment of small asteroids with orbits that approach Earth, a category to which the Kamil impactor originally belonged.
Editor’s note:
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).
Kamil crater in Google maps: (click for interactive view)
Riiiight, it’s “basic physics” — NOT:
http://wattsupwiththat.com/2009/12/27/the-unbearable-complexity-of-climate-2/
Keith Minto says:
September 24, 2010 at 7:41 pm
Most impact craters seem to be circular, indicating a direct head-on impact (especially the gravity anomaly images) rather than elliptical. Is there a sound reason for this?
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Good question, why no glancing shots.
Gravity must tear the projectile to shreads before it hits?
Wouldn’t it be, by definition, a meteorITE crater, and not a meteor crater? Once it touches ground it’s no longer a meteor.
Djozar says: Wasn’t this on the route that was proposed for humanity’s move from Africa to the Middle East about 6000 years ago?
I think you are talking about the Sahara Pump theory. It says folks moved from the Sahara out in all directions toward water; though a large group ended up along the Nile and started Pharaonic Egypt.
http://chiefio.wordpress.com/2010/08/10/cold-dry-sahara-hot-wet-savanna/
As the Sahara cooled (yes, it was hotter then, and cooling displaced the water turning it into a desert) folks abandoned the place. The likely trigger moment being the 5.9 Kiloyear Event
http://en.wikipedia.org/wiki/5.9_kiloyear_event
or about the 4000 BC when Egypt thrust itself on the scene… which might explain both the sudden onset of culture and writing AND the stories of a grand city buried under the Sahara Sands. If it were up to me, I’d be digging at the major join of some of the riverbeds under the Sahara and at the places where they enter lakebeds and / or seas. I’d bet hard money we find ‘proto-Egyptian’ construction and writing…
Given all that, I’d expect the N. Pole to have had a lot less ice then too.
To find meteorites all you need is an unchanged rocky or icy surface and a good eye. The antarctic is obviously a good place to look as they jump off the ice at you from quite a distance, but if you’re stuck in the big city where do you go?
You look for rocky mesa formations: http://tinyurl.com/37mlxln
Gary Pearse says:
September 25, 2010 at 8:15 am
Hudson Bay was the centre load point for the glaciers during the ice ages. Let’s say it was the centre for 15 of the 25 ice ages in the last 2.5 million years.
This has depressed Hudson Bay below sea level (it has risen over 200 metres in the last 7,000 years due to post-glacial rebound). The Baltic Sea, the Barents Sea, the Kara sea and other shallow continental shelf regions in the Arctic (which are very extensive) are likely the result of similar processes.
The circular features are due to highest accumulation points (which were 3 kms high over Hudson Bay and may have been two or three different ones) pushing out in all directions (and pushing down by) gravity thus forming circular features. James Bay is one of the main channels of glacial flow south (since there was much less glacier directly to the south, the main pressure differentials would have forced the glacier through this channel).
There may be an impact crater there, but no evidence at all has been found in terms of shocked rock etc while the glaciers are capable of explaining the features.
Curiousgeorge says:
We have the technology to determine point of impact if one was spotted coming in, so if there was one aimed at NYC for example, would the powers that be let the news out? What’s worse: Mass evacuation and ensuing panic/looting,etc.; or collecting the bodies and cleanup afterwards?
What if the impact site is deep ocean? Resulting in a tsunami rather than a crater. Predicting where a tsunami will do most damage is difficult since there are many factors involved.
Keith Minto says:
Most impact craters seem to be circular, indicating a direct head-on impact (especially the gravity anomaly images) rather than elliptical. Is there a sound reason for this?
IIRC it has to do with the physics of the impact event. Meteor Crater is circular but the remains of the impacting body is now believed to be part of the South rim. (Rather than in the middle as Daniel M. Barringer originally thought.)
When it comes to large craters the issue of what map projection is used is likely to be an issue too.
Alexander,
The 6000 – 10,000 year event I was talking about was time when a cyclic shift in the earth’s axis removed the rains in this part of the world and led the herders/gatherers to the east. The shift may only be a hypothesis, but the settlements of the herders of this period have been found.
Sorry; I should have read E.M. Smith’s piece before I posted.
Jimash says:
September 24, 2010 at 12:51 pm
It has nice rays.
Indeed, wich would suggest that this is a relative fresh crater, more likely less than a thousand years than ten thousand years.