Re: Large meteor, possible meteorite near Chelyabinsk, Russi
Posted: Mon Feb 18, 2013 1:54 pm
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Thanks for this, Sheershoff! It is really fascinating - but even Isheershoff wrote:There are black little stones found on the ice of Chebarkul lake. There's little chance that they're not part of the meteorite.
There are messages, not officially confirmed, that the meteorite was assigned the name of the lake. So, if the officials will confirm this, it's Chebarkul meteorite.
Local news site page autotranslated to english http://translate.google.com/translate?h ... 2Fprint%2F. It's a terrible translation, but it sheds light on the details from the site.
Just for reference, any one of my meteor cameras records about a dozen fireballs like this every year. There are literally thousands of them all over the Earth in that same time.bystander wrote:Another meteor? 'Fireballs' light up Florida sky
NBC US News | 2013 Feb 18
You have a horse dash-camChris Peterson wrote:Just for reference, any one of my meteor cameras records about a dozen fireballs like this every year. There are literally thousands of them all over the Earth in that same time.bystander wrote:Another meteor? 'Fireballs' light up Florida sky
NBC US News | 2013 Feb 18
I don't, but it's funny you mention that, because I was riding yesterday, and it was very beautiful up here, and I was thinking about the possibility of sticking a camera on the saddle horn or on my hat, and making a sort of high-speed video of the trip. If I did that, wouldn't it be amazing if I caught a meteor!neufer wrote:You have a horse dash-cam :?:Chris Peterson wrote:Just for reference, any one of my meteor cameras records about a dozen fireballs like this every year. There are literally thousands of them all over the Earth in that same time.bystander wrote:Another meteor? 'Fireballs' light up Florida sky
NBC US News | 2013 Feb 18
I think this is a particularly bad translation. I think that the original says that the pieces were found 30 -40 metres distance from the open water. Could someone who speaks Russian better than I do clarify that?Found little nuggets of 30-40 meters from the open water
Obviously misspoke and meant to say faster than the speed of sound. Nobody's perfect, after all.slee wrote:Worst sound bite? From an American broadcaster who said, "and the meteor looked like it was on fire because it was traveling faster than the speed of light."
I mean, really!
http://astrobob.areavoices.com/?blog=78068 wrote:Scientists study 53 tiny meteorites from Russian fireball
- [b][color=#0000FF]Pieces of the Russian meteorite fall are seen in a laboratory in Yekaterinburg on Monday, Feb.18, 2013. Black shock veins are visible in the broken specimen in the background if you look closely [i.e., click on photo]. Credit: AP Photo/ The Urals Federal University Press Service, Alexander Khlopotov[/color][/b]
Astrobob, February 18, 2013
<<Scientists at Urals Federal University in Yekaterinburg have examined 53 meteorite fragments taken from the perimeter of the hole in frozen Chebarkul Lake. The largest is only 7 mm (about a quarter-inch) across; the smallest about one millimeter. Many are covered with dark fusion crust, a layer of melted and blackened rock from atmospheric heating.
The little stones are a common type of meteorite called a chondrite (KON-drite) that originated in the crust of an asteroid. A long-ago impact sent a fragment of the asteroid flying toward the inner solar system where it ultimately encountered Earth last Friday.
The Russian meteorite, which may receive the name Chebarkul, after the lake and town where it was found, contains about 10% iron-nickel, magnesium-rich chrysolite and sulfite, all common materials found in stony meteorites.
Chondrites are classified according to their iron content. Those with 15-20% nickel-iron metal are iron-rich and named “H” chondrites. Meteorites with a 7-11% nickel-iron content are classified as “L” chondrites, and those with the lowest amount of iron are the “LL” variety. Based on the lab’s description, it would appear that the fireball left a trail of L-chondrite crumbs. Let’s hope the hunters and scientists can follow the trail to the bigger ones.>>
http://www.washingtonpost.com/national/health-science/crater-found-in-iowa-points-to-asteroid-break-up-470-million-years-ago/2013/02/18/545131f8-76d5-11e2-aa12-e6cf1d31106b_story.html wrote:Crater found in Iowa points to asteroid break-upClick to play embedded YouTube video.Harold Hill feeling contrite in Iowa
By Brian Vastag, The Washington Post: February 19, 2013
<<An asteroid as big as a city block smashed into what is now northern Iowa about 470 million years ago, says a Smithsonian geologist, supporting a theory that a giant space rock broke up and bombarded Earth just as early life began flourishing in the oceans. The impact dug a crater nearly four miles wide that now lies beneath the town of Decorah, said Bevan French, one of the world’s foremost crater hunters and an adjunct scientist at the National Museum of Natural History. The asteroid that carved it would have dwarfed the estimated 55-foot-wide space rock that exploded over southern Russia on Friday. The Decorah object smashed into bedrock with such force that it shattered tiny grains of minerals. French found this “shock quartz” in gravel from beneath the town, he told two dozen colleagues during a seminar at the museum last week.
Finding impact craters is rare, as erosion and the shifting of tectonic plates tend to erase them. The Decorah crater, if accepted by other scientists, would be just the 184th known, according to an international database at the University of New Brunswick. But spying the evidence of the Earth’s most dramatic explosions requires only humble equipment — a simple black microscope. As sun streamed into French’s office above Constitution Avenue one recent afternoon, he placed a glass slide under the microscope’s lens and invited a reporter to peer in. A thin slice of rock from beneath Decorah sat on the slide. Three white circles — quartz crystals no bigger than mustard seeds — popped into view. Dozens of parallel lines striped each circle: evidence of a rock-crushing pulse. “They’re shattered,” French said of the crystals. Geologists consider shock quartz near-definitive evidence of an extraterrestrial impact.
The Decorah crater lay undiscovered until now because almost none of it peeks above ground. Instead, it is filled by an unusual shale that formed after an ancient seaway sluiced into the crater, depositing sediment and an array of bizarre sea creatures that hardened into fossils, French said. This shale was the first clue that certain Iowans may be unknowingly living in a crater.
Jean Young, an amateur geologist in northern Iowa, noticed the shale about a dozen years ago, when inspecting gravel pulled up by well-drilling machines. It looked like no other rock she had seen in the region. Young sent samples to Robert McKay, a geologist at the Iowa Department of Natural Resources. McKay then pulled from his files “churn gravel” from dozens of other wells drilled in a four-township area centered on Decorah. He found the same shale in some of the other samples, too. When plotted on a map, the shale-rich borings described a “nice circular basin” about 31 / 2-miles wide, neatly bisected by the Upper Iowa River and almost completely encompassing Decorah, he said.
McKay, French and other colleagues are preparing a scientific paper describing the discovery. McKay and colleagues dubbed the black rock Winnesheik Shale and published a scientific paper describing it in 2006. But only after French recently identified the shock quartz — which was pulled from beneath the shale — did a giant impact seem more certain. “They found what would be expected from an impact,” said Michael Velbel, a Michigan State University geologist, on sabbatical at the Smithsonian, who attended French’s talk last week. “It’s clear the shale fills a crater.”
Fossils in the shale — including eel-like conodonts, worms called verimforms, and shrimp-like creatures called eurypterids — date the crater to about 470 million years ago, McKay said. This geologic period, known as the Middle Ordovician, was marked by an explosion of early life in the oceans. This period was also marred by an apparent uptick in the number of asteroid impacts on Earth. About a dozen of the planet’s known impact craters hail from that time.
In 2004, astronomers including Birger Schmitz of the University of Lund, Sweden, proposed a shocking explanation: A massive collision in the asteroid belt beyond Mars about 469 million years ago bombarded Earth with asteroid fragments. Supporting this idea: About 20 percent of all meteorites on Earth — known as “L-chondrites” — date from this period. They appear so similar as to have broken off from the same parent body. The Decorah crater may have been formed by one such fragment, French said. Even more intriguingly, this newfound crater lies on a line between two other impacts of roughly the same age: the Rock Elm crater in Wisconsin and the Ames crater in Oklahoma. A single giant asteroid may have flown in from the south, shattered and left a pockmarked trail of smoldering craters strung along about 500 miles. French labeled the possibility “stimulating speculation.” But because dating techniques render it impossible to narrow down the age of the three craters to a single century — let alone a single day — that notion probably will remain in the realm of speculation. “It’s certainly possible,” McKay said. “But trying to prove all three came down at the same time would be tough. I’m not exactly sure how we could do that.”>>
http://en.wikipedia.org/wiki/Decorah_crater wrote: <<The Decorah impact crater centered on the east side of Decorah, Iowa where an asteroid struck the Earth during the Middle Ordovician Period, 470 million years ago. It is estimated to be 3.5 miles (5.6 km) in diameter, covered by Winneshiek Shale. There is no surface evidence of the impact, the Winneshiek Shale is more than 50 feet below the bottom of the Upper Iowa River. It may be one of several Middle Ordovician that fell roughly simultaneously 469 million years ago, including the Rock Elm crater in Wisconsin and the Ames crater in Oklahoma.>>
Snow is terrible for finding fresh meteorites. They almost always punch through and become virtually impossible to find while the snow remains. This has been well demonstrated in several recent Canadian winter meteorite falls.JohnD wrote:Comment here, and on the other thread, that discovering fragments must wait until the snow has gone.
Since the best field for finding meteorites is said to be the Antarctic ice shelf, where stones are easily seen against the white, and in some sandy deserts where they are also show up in contrast, why is that so?
Once the snow had gone, the meteorites will be lost in vegetation.
geckzilla wrote:Obviously misspoke and meant to say faster than the speed of sound. Nobody's perfect, after all.slee wrote:Worst sound bite? From an American broadcaster who said, "and the meteor looked like it was on fire because it was traveling faster than the speed of light."
I mean, really!
To be fair, nothing hit the ground at 33,000 mph, and it remains uncertain if the hole in the lake was actually created by anything falling from the sky.GoldHorde wrote:I heard one broadcaster who thought the hole in the lake was proof of some weapons conspiracy because the hole was "too round" for something going 33,000 MPH! Talk about a TOTAL lack of common sense & basic physics!
Chris Peterson wrote:To be fair, nothing hit the ground at 33,000 mph, and it remains uncertain if the hole in the lake was actually created by anything falling from the sky.GoldHorde wrote:I heard one broadcaster who thought the hole in the lake was proof of some weapons conspiracy because the hole was "too round" for something going 33,000 MPH! Talk about a TOTAL lack of common sense & basic physics!
There is no indication of size of the photo above, but there is a useful inclusion of a matchstick on those below.sheershoff wrote:Studio photos of the meteorite available here
Text on Google translation of http://pavelmaltsev.ru/urfu/photo-meteo ... barkul.php
The photos were taken from different angles. Metallic inclusions meteorite glare differently depending on the viewing angle...
Below are photos of another fragment.