Research shows collision created Chelyabinsk asteroid

May 23, 2014 by Marcia Malory report
(a) The host-rock showing an equilibrated chondrite texture. (b) A shock-melt vein cutting through the host-rock. The two white dotted lines represent the boundaries between them. (c) Coarse-grained fragments and fine-grained matrix in a shock-melt vein. (d) Enlarged view of the area shown by the white rectangular in (c). Needle-like and skeletal-rhombic crystals of jadeite occur with feldspathic glass. Ol = olivine, En = enstatite, Di = diopside, Fsp = albitic feldspar, Me = Fe–Ni metal, Tro = troilite, Chr = chromite, SMV = shock-melt vein, Mtx = matrix of shock-melt vein, Jd = jadeite, Gl = feldspathic glass. Credit: Scientific Reports 4, Article number: 5033 doi:10.1038/srep05033

(Phys.org) —On February 15 2013, an asteroid exploded about 30 kilometers above Chelyabinsk, Russia. The explosion, shared on video around the world, was the Earth's second largest recorded airburst. By analyzing fragments of the meteorite that fell to Earth, Shin Ozawa at Tohoku University in Sendai, Japan and colleagues determined that the asteroid formed when a parent asteroid collided with another asteroid and then broke apart. The research appears in Scientific Reports.

When an asteroid, 17 to 20 meters in diameter, burst over the south of Chelyabinsk city, in Russia's southern Ural region, it generated shockwaves that injured more than 1000 people and damaged many buildings. Unlike many other Near Earth Objects (NEOs), the Chelyabinsk asteroid had a well-recorded trajectory, and it left fragments on the Earth. This gave scientists a unique opportunity to study its formation.

Previous studies of the asteroid's fragments had shown they contain shock-melt veins, which form when heat and pressure from an impact cause materials in a section of an asteroid to melt. Eventually, shock-melt veins lose heat to cooler surrounding rock and solidify, forming glassy structures.

Ozawa's team examined the shock-melt veins in the Chelyabinsk fragments and found they contain the mineral jadeite, which forms under extremely high pressure. Some terrestrial rocks and meteorites contain jadeite. However, when the team examined the jadeite from the Chelyabinsk meteorite under an electron microscope, they found the mineral had a unique composition and structure that indicated it had crystallized very rapidly.

By calculating the rate at which the jadeite must have solidified, the team were able to determine that the asteroid must have formed when a parent asteroid collided with a second asteroid, which was at least 150 meters in diameter and moving at a relative speed of 0.4 to 1.5 kilometers per second. A previous study of the isotopes in the meteorite had shown that a collision could have occurred up to 290 million years ago. The jadeite would have formed as the result of this collision, as the mineral would not have survived a later impact.

Earlier calculations had shown that asteroids in the have lifetimes of less than 10 million years. The researchers think the Chelyabinsk broke off from its parent after the collision and moved into an orbital resonance less than 10 million years ago. It then fell into an orbit crossing that of the Earth.

The research increases our understanding of how NEOs form and evolve. It shows that NEOs, which have the potential to strike the Earth, can survive much longer than previously believed.

Explore further: Asteroid to make close pass by Earth

More information: Jadeite in Chelyabinsk meteorite and the nature of an impact event on its parent body, Scientific Reports 4, Article number: 5033 DOI: 10.1038/srep05033

Abstract
The Chelyabinsk asteroid impact is the second largest asteroid airburst in our recorded history. To prepare for a potential threat from asteroid impacts, it is important to understand the nature and formational history of Near-Earth Objects (NEOs) like Chelyabinsk asteroid. In orbital evolution of an asteroid, collision with other asteroids is a key process. Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite. Based on the mineral assemblage and calculated solidification time of the shock-melt veins, the equilibrium shock pressure and its duration were estimated to be at least 3–12 GPa and longer than 70 ms, respectively. This suggests that an impactor larger than 0.15–0.19 km in diameter collided with the Chelyabinsk parent body at a speed of at least 0.4–1.5 km/s. This impact might have separated the Chelyabinsk asteroid from its parent body and delivered it to the Earth.

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cantdrive85
1 / 5 (9) May 23, 2014
Electric discharge can easily produce the heat and pressure required for the observation. Such a notion would falsify an entire paradigm, as such the mechanism is not even considered.
Captain Stumpy
5 / 5 (6) May 23, 2014
Electric discharge can easily produce the heat and pressure required for the observation
@cd
so what was the mechanism for the catastrophic detonation above the ground?
another thing here... if it were electrical in nature, then WHY are we finding SOLID EVIDENCE of an asteroid?
...Chelyabinsk asteroid had a well-recorded trajectory, and it left fragments on the Earth. This gave scientists a unique opportunity to study its formation
this is why people laugh at you and your EU philosophy: you are so willing to modify reality to fit your philosophy that you ignore very pertinent details as well as physical laws.

It's either that or you cannot/did not read the article...
Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite.
this was in the abstract...
guess you missed that...
and the first paragraph that said it broke apart...
??
cantdrive85
1 / 5 (8) May 23, 2014
so what was the mechanism for the catastrophic detonation above the ground?

Exploding capacitor.
if it were electrical in nature, then WHY are we finding SOLID EVIDENCE of an asteroid?

I'm not suggesting there is no meteorite, why are you? It was the asteroid which experienced electric discharge upon it.
this is why people laugh at you and your EU philosophy: you are so willing to modify reality to fit your philosophy that you ignore very pertinent details as well as physical laws.

I laugh at you because you completely misinterpret every pertinent detail or even come close to understanding the physics of what happens to a charged object when it enters an environment with a different charge.
Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite.
That "vein" is where the current flowed through to melt the mineral. It's quite clear you don't even have a rudimentary understanding of the claims made by EU.

Captain Stumpy
5 / 5 (6) May 23, 2014
I'm not suggesting there is no meteorite, why are you?
@cd
given your history, lack of clarity here, and that you believe that the moon craters were formed by electric discharge, not the asteroids etc which were observed
I laugh at you because you completely misinterpret every pertinent detail
nope. it is the details, which are mostly pseudoscience smothered in a healthy layer of BS, which are at odds with the world and reality. see Grand Canyon theories about formation on your pseudoscience site... or re-read your own arguments about how the moon craters formed

it's apparent that EU claims are nothing but PSEUDOSCIENCE wrapped in CONSPIRACY as well as smothered in physics defying feats. Your EU is debunked, and you are STILL trying to fit the data to the theory... just keep trimming the data, sparky. eventually you'll perform some fatal experiment and solve a consistently annoying problem in the world. But it will raise the world IQ exponentially & fertilize too. win win
yep
1 / 5 (3) May 27, 2014
Captain, I see your still working hard as High Priest of the big bang dark black magic cult leftovers from last century. All praise those who know better than everyone else.
This article is quite informative.
Shock metamorphism of some minerals
http://www.geolog...inal.pdf
Interesting how some work is carried out.
"The principle of the electric gun is to vaporise a
thin metal foil by rapid electric discharge of a capacitor.
The high electrical current leads to the instantaneous va-
porisation of the foil and the production of a shock wave"
Funny, that comets can have an ionized tail a million miles long but the the idea that a comet or meteor entering the atmosphere might be experiencing a differential charge burst is outrageous.
Fun with ultracapacitors
http://www.youtub...MF3VkI6U
"Wow! That beaver took a pounding."
cantdrive85
1 / 5 (2) May 27, 2014
Funny, that comets can have an ionized tail a million miles long but the the idea that a comet or meteor entering the atmosphere might be experiencing a differential charge burst is outrageous.


It's called dogma and belief, some of us know the difference between real evidence and those who can shout louder from their pulpit...

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