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Meteorite fall in Chelyabinsk!


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Have you ever gone primitive camping? If you have, you should know that you don't use sedimentary rocks such as sandstone for the fire ring because if you do they might explode. Combustion is not need

Today registered a decline metiarita! Flash seen for 300 miles! Does not work mobile. There are wounded from cuts of broken glass! The evening will fly folder, NASA will be broadcast live!   Here is

Wondering how quickly this event will get political. The far righty are always accusing the scientific community of sensationalism. They want to defund Nasa because they have provided evidence which

Even if they're mostly metal or rock, there is still a chance of pockets of ice or frozen gas within. The heat from friction builds up enough pressure to cause an explosion.

Found this below from here . Not very convincing.

 

 

 

Why do asteroids burn up in the atmosphere?
Answer:

The answer is NOT friction as many people believe.

 

 

When a meteoroid enters the upper atmosphere of Earth, it is travelling

at a very high speed; in the neighborhood of 30,000 MPH. As it enters

the atmosphere the air in front of it is compressed. When a gas is

compressed, its temperature rises. This very hot air then heats the

leading edge of the meteoroid as high as 3,000 degrees F (1,650 degrees

C).

 

Then enough heat is generated that the meteoroid catches on

fire and eventually vaporizes (disintegrates). Most meteoroids that

enter burn up completely, a small percentage make it to the ground where

they remain as small, extremely hot rocks, and an even smaller

percentage actually cause catastrophic disasters.

__________________________

There

are inaccuracies in the explanation above. The meteoroids that make it

to the ground, at least the small ones, are not extremely hot. Just

think, once the object has been reduced to a few ounces or a few pounds,

it is not going to heat up any further in the last few miles before

impacting the Earth. It will most likely cool down. Only the very large

ones will cause devastation and impact craters. and they will still most

likely not be hot. How hot can an object of a few tons that was

travelling through cold space get after a few minutes of causing heat by

compressing the air it passes through? Like ice, only the surface

melts. The interior will still be cold until its internal -250 degree C

temperature is raised. That could take a very long time for a large

object.

All this looks like coming from "common sense". i see no scientific explanation.

 

When one reads from wiki:

 

The total energy released was equivalent to nearly 500 kilotons of TNT,[10][1][2] which would make it 20–30 times more powerful than the atomic bombs detonated at Hiroshima and Nagasaki.[1][2][11][10]

To me that is not an explosion caused by thermal (chemical) reaction.

More like a hydrogen bomb.

Edited by michel123456
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-----------------------
Found this about Barringer Meteorite Crater in Arizona:

In 1960, Eugene Shoemaker, Edward Chao and David Milton
were responsible for the discovery of a new mineral at the Barringer
crater. This mineral, a form of silica called “coesite”, had first been
created in a laboratory in 1953 by chemist Loring Coes. Its formation
requires extremely high pressures and temperatures, greater than any
occurring naturally on earth. Coesite and a similar material called
“stishovite” have since been identified at numerous other suspected
impact sites, and are now accepted as indicators of impact origin.


Finally, in 1963, Eugene Shoemaker published his landmark
paper analyzing the similarities between the Barringer crater and
craters created by nuclear test explosions in Nevada. Carefully mapping
the sequence of layers of the underlying rock, and the layers of the
ejecta blanket, where those rocks were deposited in reverse order, he
demonstrated that the nuclear craters and the Barringer crater were
structurally similar in nearly all respects.
His paper provided the
clinching arguments in favor of an impact, finally convincing the last
doubters.

From here (emphasizing mine)

 

--------------------

And the "does not work mobile" from the OP is also interrogating.

Edited by michel123456
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A credible scientific explanation for the Russian meteor will be difficult

NASA says it weighed 10,000 tons before it entered the Earth's atmosphere,

Russian scientist say it was 10 tons that mean 99.9% of the meteor would

have to evaporated before it got close to Earth looking at work done by

gravity on the meteor and slowing due to air resistance would have to

account for the evaporation energy of almost the entire meteor. Also

the meteor did not travel far from being a smaller glowing object to

a massive glowing object followed by a large explosion, the energy

numbers have to make sense for this whole event. The composition

of the meteor fragments would also have to justify the blinding white

light from the meteor. For the Tunguska event of 1908 there was never

a credible scientific explanation given for it.

 

 

http://www.telegraph.co.uk/science/space/9874662/Russian-meteor-exploded-with-force-of-30-Hiroshima-bombs.html

 

http://www.telegraph.co.uk/science/space/9874790/Russian-meteor-lack-of-fragments-sparks-conspiracy-theories.html

 

http://www.ibtimes.com/russias-other-meteor-crash-mysterious-1908-tunguska-event-1088770

Edited by Semjase
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But heat comes from the outside and the meteorite is supposed to be solid rock. It is not full of kerozene.

 

Have you ever gone primitive camping? If you have, you should know that you don't use sedimentary rocks such as sandstone for the fire ring because if you do they might explode. Combustion is not needed. All that is needed is the water that's bound in the rock to be released as steam. The internal pressure that results, coupled with the inherent weakness of those rocks, makes the rocks explode.

 

That is what happened with this meteor. Carbonaceous chondrites make sandstone look downright sturdy, and some contain quite a bit of water and other volatiles.

 

 

Found this below from here . Not very convincing.

 

All this looks like coming from "common sense". i see no scientific explanation.

 

It's answers.com. What do you expect? Answers?

 

Bon jour.

 

 

To me that is not an explosion caused by thermal (chemical) reaction.

More like a hydrogen bomb.

 

You're forgetting about kinetic energy, [math]KE=\frac 1 2 mv^2[/math]. This meteor had a mass of about 10,000 short tons and was going about 47,000 mph. That represents a lot of energy, about 30 times the amount of energy released by the Hiroshima bomb.

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This is the most interesting video I've seen of the

meteor mind blowing if true but most likely fake

 

http://www.youtube.com/watch?v=nXdJ7wm4Opk

 

Certainly interesting viewing !

 

Has anybody yet confirmed or disproved a link between the Russian Exploding meteor and the passing asteroid skimming the upper satellite orbits. It otherwise seems remarkably coincidental !

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Has anybody yet confirmed or disproved a link between the Russian Exploding meteor and the passing asteroid skimming the upper satellite orbits. It otherwise seems remarkably coincidental !

The asteroid flyby and Russian meteor explosion had significantly different trajectories, showing that they were completely unrelated events, NASA officials said.

http://www.space.com/19838-russian-meteor-blast-bigger-size.html

 

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I am no expert, but I will still give my 2 cents on why such a rock may cause a sudden explosion.

 

The following sequence of events seems likely to me:

 

1. Rock enters atmosphere.

2. Air gets compressed in front of rock. Heats up a lot.

3. Rock also heats up, but only on outside.

4. Large temperature difference cracks the rock (like a thermal shock). It breaks.

5. All the rock fragments now have a MUCH larger frontal surface area, compressing much more air, turning much more kinetic energy into heat in a much shorter time. It is so sudden, that this is observed as an explosion.

 

Once again: I am not an expert on meteorites, but I know a thing or two about heat transfer... and that tells me that a few seconds is a very short time to boil any water inside a rock. Even if the temperature reaches thousands of degrees, you have to deal with heat transfer. I would be surprised if the temperature a few centimeters inside the rock would change at all so quickly. If this is a big rock, then I don't think that expanding steam would be the cause of the rock to break up.

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I am no expert, but I will still give my 2 cents on why such a rock may cause a sudden explosion.

 

The following sequence of events seems likely to me:

 

1. Rock enters atmosphere.

2. Air gets compressed in front of rock. Heats up a lot.

3. Rock also heats up, but only on outside.

4. Large temperature difference cracks the rock (like a thermal shock). It breaks.

5. All the rock fragments now have a MUCH larger frontal surface area, compressing much more air, turning much more kinetic energy into heat in a much shorter time. It is so sudden, that this is observed as an explosion.

 

Once again: I am not an expert on meteorites, but I know a thing or two about heat transfer... and that tells me that a few seconds is a very short time to boil any water inside a rock. Even if the temperature reaches thousands of degrees, you have to deal with heat transfer. I would be surprised if the temperature a few centimeters inside the rock would change at all so quickly. If this is a big rock, then I don't think that expanding steam would be the cause of the rock to break up.

You made your own explanation, does that mean that you too feel a lack of information?

 

i can accept any explanation for the explosion but i need something that explains the flash. The light was so bright that it produced shadows (IOW it was brighter than the sun). You don't get such an effect with a simple fire.

Edited by michel123456
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i can accept any explanation for the explosion but i need something that explains the flash. The light was so bright that it produced shadows (IOW it was brighter than the sun). You don't get such an effect with a simple fire.

 

It wasn't fire. It was "just" kinetic energy. The cross sectional surface area suddenly increased by orders of magnitude when that rock exploded (no fire needed). That huge increase in surface area meant a huge increase in the rate at which energy was transferred to the atmosphere. Kaboom, and ka-flash.

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Ka-flash I don't know why. When a pressure cooker explodes, there is no light.

 

You are still ignoring kinetic energy. Your pressure cooker is not going about 20 kilometers per second. That meteor was.

 

[imath]1/2\,m\,v^2[/imath] makes for a lot of kinetic energy when both m and v are rather large. In this case, 10,000 tons moving at 20 km/s represented a whole lot of kinetic energy, about the same as that released by 30 Hiroshima-type bombs. When that meteor blew up, the rate at which energy was transferred to the atmosphere went up by orders of magnitude because the tiny pieces had a whole lot more surface area than did the meteor right before it blew up. The bulk of that energy transfer was in the form of heat.

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Makes sense.

 

@Michel: The flash of light is essentially caused due to a very large amount of energy being transferred to the surroundings in a very short amount of time - due to increased relative surface area. Think about burning pieces of wood - if you set fire to a very large piece of wood (which has a high volume in relation to its surface area) then it will take a long time for it to burn and consequently the flame intensity (brightness) will be relatively low over a small amount of time. However, if you burn very small pieces of wood (which have high surface area to volume ratios) then the brightness of the flame per unit time will be relatively larger than the former scenario.

 

It's the same situation with this meteorite - as it has exploded into smaller fragment, thus it's overall surface area to volume ratio will be larger than when it was a single rock, thus energy is transferred at a faster rate; hence the light "flash".

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Certainly interesting viewing !

 

Has anybody yet confirmed or disproved a link between the Russian Exploding meteor and the passing asteroid skimming the upper satellite orbits. It otherwise seems remarkably coincidental !

 

 

Yes me!!!

I am uploading a video to youtube to explain it, gonna take another 70 minutes, huge file 1 GB for 3 mins of video lol.

Never made a video to upload before so I have a lot to learn there.

I believe I have proved it could be linked..

Will post a link when it is ready.

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Kaboom say yes.

 

Ka-flash I don't know why. When a pressure cooker explodes, there is no light.

 

True. And the reason is simple. There is not enough energy per kilogram of material to make it hot enough to make it glow.

 

A pressure cooker, at 250 C contains an approximated T*Cp = 250*4180 = 1 MJ/kg of thermal energy. If we include some energy from the steam pressure, we can increase that. And for the sake of the argument, let's just say that a pressure cooker can contain twice as much energy (it's actually can't, but my point will still stand). So, 2 MJ/kg is your energy per mass in a pressure cooker, and that won't flash as bright as the sun. True.

 

According to the telegraph, who cite NASA, the rock was going 44000 miles/hr, or 70811 km/hr, or 19.7 km/s. The kinetic energy contained in a kilogram of rock is then 0.5*m*v^2 = 0.5*1*19700^2 = 194 MJ/kg, about 100 times more than your pressure cooker.

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Informations diverge:

 

10 tonnes from the ones (that is ten thousands kilograms)

10,000 tons (I suppose meaning short tons) from the others = approx 9,072 tonnes (that is nine millions kilograms)

 

That's a difference of 10^3



------------------

From the very little info I can get it seems to me the most probable explanation is that the ionized gases of atmosphere exploded, producing a little sun for 5 seconds.



trace.jpg

This above a rotaded image of the trace in the russian sky. (original image from wiki here)

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Informations diverge:

 

10 tonnes from the ones (that is ten thousands kilograms)

10,000 tons (I suppose meaning short tons) from the others = approx 9,072 tonnes (that is nine millions kilograms)

 

That's a difference of 10^3

 

 

------------------

From the very little info I can get it seems to me the most probable explanation is that the ionized gases of atmosphere exploded, producing a little sun for 5 seconds.

 

 

(image removed by mod - can be seen in the post above).

 

This above a rotaded image of the trace in the russian sky. (original image from wiki here)

 

 

 

. ---------- Michel ----------

 

 

. Are we going to live.? or are we all going to die ?

 

 

. ----------------------------------------

 

.

Edited by CaptainPanic
We only need such a huge picture once
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Michel

 

 

Are we going to live.? or are we all going to die ?

 

Mike

 

Is this trolling.? or Are you just confused what the topic is about?

 

 

We are all going to die. Eventually. But that is really another topic, methinks. Now, let's talk about meteors, asteroids and explosions again.

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As Captain said we are all going to die but not all together at the same time which is what frightens people. That's another topic indeed. And that is not related with the asteroid. As pointed above injuries were caused by curiosity and buildings. And lack of information on what to do when a flash occurs.



On the last picture one can observe the fumes make a spiral. As if the asteroid was rotating upon itself, like a spinning bullet from a rifle. The straight path indicates the same. (or maybe - I don't see clearly- maybe it is a double spiral rotating clockwise & counter clockwise.

 

The double fume is intriguing anyway.

Edited by michel123456
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!

Moderator Note

 

Connexions with between 2012 DA14 and Chelyabinsk Meteorite are speculative at best and the discussion has been moved to speculations.

 

http://www.scienceforums.net/topic/73028-2012-da14-any-link-with-chelyabinsk-meteorite/

 

Please try to keep to the topic of the Chelyabinsk Meteorite.

 

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