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    Chelyabinsk meteor

    Aristide
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    Post  Aristide on Sun Nov 24, 2019 10:55 am

    Maybe you remember the 2013 chelyabinsk meteor, which caused massive damage and is teh biggest witnessed meteorite fall captured on camera.

    I was unaware that many citizens of the city collected pieces of the meteorite. Some even made a business out of it and search the huge stray field for meteorite pieces.

    I was able to contact someone from the city who has a alot of it and will recieve my piece next week.

    What i find funny is, that russia has no export ban of this. Russia had some spectacular meteor impacts in recent history. From Chelyabinsk, to Sikhote Alin. Some of them like Brahin are super rare pallasite meteorites.

    They are sold to western europe and USA for collectors. Here they are made collection objects and in some instances art and rings, necklaces ect. I own alot of this stuff. For example several individual meteorites from russia, ring made from
    meteorite iron from russia, and a necklace made from meteoritic chondrules also from russia.


    Most other developed nations dont allow export in such numbers.
    Regular
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    Post  Regular on Sun Nov 24, 2019 2:36 pm

    And most of the countries don't have so many scammers.

    For how authoritative Russia is, there's plenty of laws that are not reinforced or overlooked.

    Good luck with your purchase
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    Post  Isos on Sun Nov 24, 2019 2:40 pm

    You will receive a basic rock lol1 lol1
    Aristide
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    Post  Aristide on Sun Nov 24, 2019 3:53 pm

    Regular wrote:And most of the countries don't have so many scammers.

    For how authoritative Russia is, there's plenty of laws that are not reinforced or overlooked.

    Good luck with your purchase

    You cant scam a meteorite. No earth rock has a so called fusion crust, which is created through extreme aerodynamic forces through entry in the atmosphere. The surface is melted through the extreme heat, actually hotter than the surface
    of the sun. Its movement through the athmosphere makes it orientated. The fusion crust is only a mm thin, since the inside the meteorite stays cool.

    The sale runs through a french meteorite dealer who checks the objects before payment. Did this several times before and have excellent experience with russian meteorite sellers.
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    Post  GarryB on Sun Nov 24, 2019 11:13 pm

    Wow... you are surprised that Russia is a capitalist country where people who find meteorites can sell them if they want... what a bunch of communist uncivilised bastards... the west is... for having such laws.
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    Post  Aristide on Mon Nov 25, 2019 6:17 am

    GarryB wrote:Wow... you are surprised that Russia is a capitalist country where people who find meteorites can sell them if they want... what a bunch of communist uncivilised bastards... the west is... for having such laws.

    What?
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    Post  GarryB on Mon Nov 25, 2019 7:22 am

    The west.... the land of the free... home of democracy and the pinnacle of human civilisation bans the export of rocks that fall from the space... what happened to freedom of choice and commerce and market economy and all the bullshit the west spouts when someone else wont sell them what they want....
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    Post  George1 on Mon Nov 25, 2019 7:56 am

    Aristide wrote:Maybe you remember the 2013 chelyabinsk meteor, which caused massive damage and is teh biggest witnessed meteorite fall captured on camera.

    I was unaware that many citizens of the city collected pieces of the meteorite. Some even made a business out of it and search the huge stray field for meteorite pieces.

    I was able to contact someone from the city who has a alot of it and will recieve my piece next week.

    What i find funny is, that russia has no export ban of this. Russia had some spectacular meteor impacts in recent history. From Chelyabinsk, to Sikhote Alin. Some of them like Brahin are super rare pallasite meteorites.

    They are sold to western europe and USA for collectors. Here they are made collection objects and in some instances art and rings, necklaces ect. I own alot of this stuff. For example several individual meteorites from russia, ring made from
    meteorite iron from russia, and a necklace made from meteoritic chondrules also from russia.


    Most other developed nations dont allow export in such numbers.

    you can go to the site of the impact and collect some soil if you want for free
    Aristide
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    Post  Aristide on Mon Nov 25, 2019 8:25 pm

    George1 wrote:
    Aristide wrote:Maybe you remember the 2013 chelyabinsk meteor, which caused massive damage and is teh biggest witnessed meteorite fall captured on camera.

    I was unaware that many citizens of the city collected pieces of the meteorite. Some even made a business out of it and search the huge stray field for meteorite pieces.

    I was able to contact someone from the city who has a alot of it and will recieve my piece next week.

    What i find funny is, that russia has no export ban of this. Russia had some spectacular meteor impacts in recent history. From Chelyabinsk, to Sikhote Alin. Some of them like Brahin are super rare pallasite meteorites.

    They are sold to western europe and USA for collectors. Here they are made collection objects and in some instances art and rings, necklaces ect. I own alot of this stuff. For example several individual meteorites from russia, ring made from
    meteorite iron from russia, and a necklace made from meteoritic chondrules also from russia.


    Most other developed nations dont allow export in such numbers.

    you can go to the site of the impact and collect some soil if you want for free

    Yes but you must pay flight, invest time, money ect.
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    Post  Tsavo Lion on Tue Dec 03, 2019 4:34 pm

    I own alot of this stuff. For example several individual meteorites from russia, ring made from meteorite iron from russia, and a necklace made from meteoritic chondrules also from russia.
    In Russia, private owning of a meteorite/pieces of it is illegal- I remember reading that the authorities demanded the surrender of all of them after that incident. Any1 trying to mail it abroad risks getting into legal trouble- the customs check all outgoing parcels & can distinguish the fake from the real.
    There are numerous processes on Earth, such as chemical weathering, that cause rocks to have coatings and rinds. Some of these, particularly desert varnish, can look remarkably like a meteorite fusion crust. http://meteorites.wustl.edu/realities.htm

    "The only way to tell for sure is to look at the specimen under a microscope," says Starkey. "Some minerals, such as biotite, only form on Earth. A specialist will be able to identify those and then rule out whether it's a meteorite. The only truly definitive test, though, is to examine the specimen for oxygen isotopes. Anything that originated on earth will fall within a particular range of isotopes. Anything outside this range will mean it is extra-terrestrial in origin."
    https://www.theguardian.com/science/shortcuts/2013/feb/18/russian-meteorite-fragments-stratospheric-prices

    The "fragments" being sold may be thermally processed to look like authentic. It's a lot easier than making artificial gemstones that r no worse than their natural counterparts:
    https://www.gia.edu/gem-synthetic

    https://www.miadonna.com/pages/stone-guide-lab-created-gemstones

    http://www.jewelrywise.com/just-for-you/article/what-you-need-to-know-about-lab-created-stones

    https://www.cnbc.com/2018/05/11/diamond-market-may-be-warming-to-lab-made-gems.html

    Some may even be made by u:
    https://www.thoughtco.com/how-to-make-faux-gems-from-crystals-607668

    So, keep wasting ur $.
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    Post  Aristide on Tue Dec 03, 2019 7:49 pm

    Tsavo Lion wrote:
    I own alot of this stuff. For example several individual meteorites from russia, ring made from meteorite iron from russia, and a necklace made from meteoritic chondrules also from russia.
    In Russia, private owning of a meteorite/pieces of it is illegal- I remember reading that the authorities demanded the surrender of all of them after that incident. Any1 trying to mail it abroad risks getting into legal trouble- the customs check all outgoing parcels & can distinguish the fake from the real.
    There are numerous processes on Earth, such as chemical weathering, that cause rocks to have coatings and rinds. Some of these, particularly desert varnish, can look remarkably like a meteorite fusion crust. http://meteorites.wustl.edu/realities.htm

    "The only way to tell for sure is to look at the specimen under a microscope," says Starkey. "Some minerals, such as biotite, only form on Earth. A specialist will be able to identify those and then rule out whether it's a meteorite. The only truly definitive test, though, is to examine the specimen for oxygen isotopes. Anything that originated on earth will fall within a particular range of isotopes. Anything outside this range will mean it is extra-terrestrial in origin."
    https://www.theguardian.com/science/shortcuts/2013/feb/18/russian-meteorite-fragments-stratospheric-prices

    The "fragments" being sold may be thermally processed to look like authentic. It's a lot easier than making artificial gemstones that r no worse than their natural counterparts:  
    https://www.gia.edu/gem-synthetic

    https://www.miadonna.com/pages/stone-guide-lab-created-gemstones

    http://www.jewelrywise.com/just-for-you/article/what-you-need-to-know-about-lab-created-stones

    https://www.cnbc.com/2018/05/11/diamond-market-may-be-warming-to-lab-made-gems.html

    Some may even be made by u:
    https://www.thoughtco.com/how-to-make-faux-gems-from-crystals-607668

    So, keep wasting ur $.  

    You always amuse me.

    The mail does not list it as meteorite of course. It comes with normal letter.

    2nd trading meteorites is business here. You cant fake widmannstaettsche lines. They form when metal cools down extremly slow. 1 degree celsius by 1 million years.

    It just bogs you that we walk around russian custom checks.Very Happy
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    Post  Tsavo Lion on Tue Dec 03, 2019 10:56 pm

    The mail does not list it as meteorite of course. It comes with normal letter.
    They X-ray all letters, whatever the customs form say or even if there's no such form.
    I could care less if they miss them.
    But beware- anything can be faked.
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    Post  GarryB on Wed Dec 04, 2019 1:58 am

    They form when metal cools down extremly slow. 1 degree celsius by 1 million years.

    And how does that make it a rock from space... what part of space cools down one degree C every million years?

    Most rocks in space are not fixed and stable... they roll... so the side facing the sun will be heated to hundreds of degrees C, while the side not facing the sun will cool to hundreds of degrees C below zero... any decent rate of spin will mean it will remain heated most of the time and for small rocks the suns heat should heat the whole object and keep it rather hot.

    Rocks from deep space far away from the sun will be very cold and remain very cold all the time.

    Rocks coming through our atmosphere will be rapidly heated by friction, but with a large object that explodes above the ground half will be super heated in a few seconds... but it will be like a frozen turkey with one side burnt with a blow torch... the centre and the back of it will remain frozen solid... and when it shatters and the pieces fall they wont be moving at 20km per second any more... otherwise you would not find them within 10m of the surface... so these slow falling frozen pieces of rock would be warmed by the atmosphere as they fell... they will be minus 100 degrees C or colder in perhaps -30 to plus 20 degrees on earths surface... so remind me again... where this 1 degree heating or cooling for every million years comes from...
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    Post  Aristide on Wed Dec 04, 2019 5:49 am

    Tsavo Lion wrote:
    The mail does not list it as meteorite of course. It comes with normal letter.
    They X-ray all letters, whatever the customs form say or even if there's no such form.
    I could care less if they miss them.
    But beware- anything can be faked.

    They dont. It just runs through. Russia is main hub for meteorite trade in the world.

    And no, this cant be fake.

    The formation of Ni-poor kamacite proceeds by diffusion of Ni in the solid alloy at temperatures between 700 and 450 °C, and can only take place during very slow cooling, about 100 to 10,000 °C/Myr, with total cooling times of 10 Myr or less.[12] This explains why this structure cannot be reproduced in the laboratory.

    The crystalline patterns become visible when the meteorites are cut, polished, and acid etched, because taenite is more resistant to the acid.

    Must really hurt you.
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    Post  Aristide on Wed Dec 04, 2019 5:58 am

    GarryB wrote:
    They form when metal cools down extremly slow. 1 degree celsius by 1 million years.

    And how does that make it a rock from space... what part of space cools down one degree C every million years?

    Most rocks in space are not fixed and stable... they roll... so the side facing the sun will be heated to hundreds of degrees C, while the side not facing the sun will cool to hundreds of degrees C below zero... any decent rate of spin will mean it will remain heated most of the time and for small rocks the suns heat should heat the whole object and keep it rather hot.

    Rocks from deep space far away from the sun will be very cold and remain very cold all the time.

    Rocks coming through our atmosphere will be rapidly heated by friction, but with a large object that explodes above the ground half will be super heated in a few seconds... but it will be like a frozen turkey with one side burnt with a blow torch... the centre and the back of it will remain frozen solid... and when it shatters and the pieces fall they wont be moving at 20km per second any more... otherwise you would not find them within 10m of the surface... so these slow falling frozen pieces of rock would be warmed by the atmosphere as they fell... they will be minus 100 degrees C or colder in perhaps -30 to plus 20 degrees on earths surface... so remind me again... where this 1 degree heating or cooling for every million years comes from...


    God Gary, i hate to feel so superior always.

    Metal rich asteroids form in larger asteroids which could be described as small plamets. At their formation they heated up to several thousand degrees. Radioactive decay heated them further up, which melted their interior. Heavy elements sunk to center. Similar to Earth with a metal rich core. Intact objects of this size are Vesta, Psyche and Ceres for example.

    Since they are several hundred km big the internal cooling took many million years. Now constant collissions broke some objects up, which is tje scource of 90% of the meteorites we find on earth. The Cheliyabinsk meteor for example was once material that formed inside a very large object and was formed in several km deep.


    Gary with all due respect, but thats basic astronomy in french schools in 10th grade. What do you guys learn in New Zealand?


    As for entry of earth atmosphere. Only a very thin layer gets heated in the way through the atmosphere. Its simply too quick. The so called fusion crust never exceed 2 or 3 mm.

    Im always happy ro lecture people from less fortunate countries, which cant afford high education.
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    Post  Tsavo Lion on Wed Dec 04, 2019 6:14 am

    U need to include ur sources- don't plagiarize what others wrote as ur own. Didn't they teach that at school?https://en.wikipedia.org/wiki/Widmanst%C3%A4tten_pattern#Lamellae_formation_mechanism

    Only a very thin layer gets heated in the way through the atmosphere.
    then how do those bigger rocks explode from the heat?
    How big a fragment can be mailed in a letter? Pl. send some pics from ur collection.
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    Post  Aristide on Wed Dec 04, 2019 6:23 am

    Tsavo Lion wrote:U need to include ur sources- don't plagiarize what others wrote as ur own. Didn't they teach that at school?https://en.wikipedia.org/wiki/Widmanst%C3%A4tten_pattern#Lamellae_formation_mechanism

    Only a very thin layer gets heated in the way through the atmosphere.
    then how do those bigger rocks explode from the heat?
    How big a fragment can be mailed in a letter? Pl. send some pics from ur collection.

    Dear god...i hate to teach elderly people...bigger rocks dont explode by the heat but because the aerodynamic forces. The rapid deccelartion starts to frakture the object by its way through atmosphere.

    Most of my collectioin is between 4 and 50 g. I can post some pics at evening when i come home.
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    Post  Tsavo Lion on Wed Dec 04, 2019 6:46 am

    i hate to teach elderly people...bigger rocks dont explode by the heat but because the aerodynamic forces. The rapid deccelartion starts to frakture the object by its way through atmosphere.
    Stop patronizing me & do ur homework: It's The high-pressure air that is forced into the nooks and crannies of the meteor breaks up the space rock in Earth's upper atmosphere, ..
    https://www.space.com/39244-meteors-explode-in-earth-atmosphere.html

    The study is also quick to note that this type of airborne disintegration is only likely to happen with smaller objects, while particularly large and strong “planet killer” rocks will almost certainly remain unaffected.
    https://bgr.com/2017/12/08/earth-noise-natural-phenomenon-recorded-hum/

    https://www.bbc.com/news/science-environment-47607696


    Last edited by Tsavo Lion on Wed Dec 04, 2019 6:52 am; edited 1 time in total (Reason for editing : add link)
    Aristide
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    Post  Aristide on Wed Dec 04, 2019 6:53 am

    Tsavo Lion wrote:
    i hate to teach elderly people...bigger rocks dont explode by the heat but because the aerodynamic forces. The rapid deccelartion starts to frakture the object by its way through atmosphere.
    Stop patronizing me & do ur homework: It's The high-pressure air that is forced into the nooks and crannies of the meteor breaks up the space rock in Earth's upper atmosphere, ..
    https://www.space.com/39244-meteors-explode-in-earth-atmosphere.html

    The study is also quick to note that this type of airborne disintegration is only likely to happen with smaller objects, while particularly large and strong “planet killer” rocks will almost certainly remain unaffected.
    https://bgr.com/2017/12/08/earth-noise-natural-phenomenon-recorded-hum/

    Your link says exactly what i said. Aerodynamic forces, not heat breaks them apart.
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    Post  Tsavo Lion on Wed Dec 04, 2019 7:11 am

    Heat also helps- the hot gases near the object penetrate it easier. Besides, the resulting smaller fragments heat up before hitting the ground- which may or may not alter their structure, depending on what they r made of.
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    Post  Aristide on Wed Dec 04, 2019 7:42 pm

    Tsavo Lion wrote:Heat also helps- the hot gases near the object penetrate it easier. Besides, the resulting smaller fragments heat up before hitting the ground- which may or may not alter their structure, depending on what they r made of.

    Got my mail from Russia today.

    Amazing LL chondrite from Cheliyabinsk

    Chelyabinsk meteor E2jafy54

    Perfect fusion crust and even a visible chondrule.
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    Post  GarryB on Thu Dec 05, 2019 1:02 am

    Metal rich asteroids form in larger asteroids which could be described as small plamets. At their formation they heated up to several thousand degrees. Radioactive decay heated them further up, which melted their interior. Heavy elements sunk to center. Similar to Earth with a metal rich core. Intact objects of this size are Vesta, Psyche and Ceres for example.

    Oh please... jnr... you can describe them as chocolate sundaes if you want... even the biggest asteroid is not a planet... most of them are not even round.

    Why do you think their formation heated them up?

    Kinetic heat doesn't last very long and they don't have enough mass to conform to a spherical shape let alone the mass to have a melted core.

    Our moon is enormous compared with any Asteroid and it is solid to the core because a hot core requires mass... the bigger an object the more mass it has... once it gets beyond a certain mass then gravity shapes it and forces it to become round... once it is big enough to become round the bigger you make it the longer its core will remain hot after it is created and the bigger it is the longer it will keep its molten core... it is all about surface area... smaller mass objects radiate heat faster so their cores cool down much faster too.


    Since they are several hundred km big the internal cooling took many million years.

    Ah bullshit... unless it is orbiting a massive object like Jupiter or Saturn in an eliptical orbit where tidal forces stretch and crush it creating friction and therefore also heat an object in space will cool fairly rapidly... a rock much smaller than a moon even faster.

    Now constant collissions broke some objects up, which is tje scource of 90% of the meteorites we find on earth.

    Why would constant collisions be necessary to make small meteorites?

    Even quite large meteors explode on reentry and become small meteorites. Collisions in space would be relatively rare... the distance between asteroids in the Asteroid belt is enormous... standing on one you probably would see any others... they are relatively small and too far apart.

    The Cheliyabinsk meteor for example was once material that formed inside a very large object and was formed in several km deep.

    Oh please... what high school did it go to and what was the name of the first girl it kissed?

    Gary with all due respect, but thats basic astronomy in french schools in 10th grade. What do you guys learn in New Zealand?

    Perhaps that is why there are so many French Astronomy experts...

    As for entry of earth atmosphere. Only a very thin layer gets heated in the way through the atmosphere. Its simply too quick. The so called fusion crust never exceed 2 or 3 mm.

    WOW... thanks for that explanation because I clearly didn't know that... my example of using a blow torch for a few seconds on a frozen turkey was way off... NOT.

    Im always happy ro lecture people from less fortunate countries, which cant afford high education.

    Yeah, that will help you win friends and impress girls... BTW which University did you attend...

    Dear god...i hate to teach elderly people...bigger rocks dont explode by the heat but because the aerodynamic forces. The rapid deccelartion starts to frakture the object by its way through atmosphere.

    And of course a genius like you understands that not every object entering the earths atmosphere is solid or rock... the object that exploded over Tunguska in 1908 was likely an iceball comet type object that shattered more than a dozen kms from the ground... when I say shattered I mean over 2,000 square kms of forest flattened and a glow in the night sky as far away as London... but no crater.

    Your link says exactly what i said. Aerodynamic forces, not heat breaks them apart.

    Well not really.... you make it sound like they all explode and all that ever hits the ground is little pieces... there are enough enormous craters still visible on earth to prove that to be wrong.

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    Post  Tsavo Lion on Thu Dec 05, 2019 5:04 am

    there are enough enormous craters still visible on earth to prove that to be wrong.
    https://en.wikipedia.org/wiki/Meteor_Crater

    https://meteorcrater.com/

    https://en.wikipedia.org/wiki/List_of_impact_craters_on_Earth

    Even Venus, with its thicker atmosphere & 91% of the surface gravity of Earth, has big craters:
    http://coolcosmos.ipac.caltech.edu/ask/48-How-strong-is-the-gravity-on-Venus-

    There are about 1000 craters identified on the surface of Venus.
    Crater Mead is the largest known crater on Venus,.. It measures 280 km in diameter, and contains several concentric rings.

    https://www.universetoday.com/22521/craters-on-venus/

    https://solarsystem.nasa.gov/resources/2267/margaret-mead-crater-on-venus/

    https://en.wikipedia.org/wiki/List_of_craters_on_Venus



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    Post  Aristide on Thu Dec 05, 2019 6:00 am

    GarryB wrote:
    Metal rich asteroids form in larger asteroids which could be described as small plamets. At their formation they heated up to several thousand degrees. Radioactive decay heated them further up, which melted their interior. Heavy elements sunk to center. Similar to Earth with a metal rich core. Intact objects of this size are Vesta, Psyche and Ceres for example.

    Oh please... jnr... you can describe them as chocolate sundaes if you want... even the biggest asteroid is not a planet... most of them are not even round.

    Why do you think their formation heated them up?

    Kinetic heat doesn't last very long and they don't have enough mass to conform to a spherical shape let alone the mass to have a melted core.

    Our moon is enormous compared with any Asteroid and it is solid to the core because a hot core requires mass... the bigger an object the more mass it has... once it gets beyond a certain mass then gravity shapes it and forces it to become round... once it is big enough to become round the bigger you make it the longer its core will remain hot after it is created and the bigger it is the longer it will keep its molten core... it is all about surface area... smaller mass objects radiate heat faster so their cores cool down much faster too.


    Since they are several hundred km big the internal cooling took many million years.

    Ah bullshit... unless it is orbiting a massive object like Jupiter or Saturn in an eliptical orbit where tidal forces stretch and crush it creating friction and therefore also heat an object in space will cool fairly rapidly... a rock much smaller than a moon even faster.

    Now constant collissions broke some objects up, which is tje scource of 90% of the meteorites we find on earth.

    Why would constant collisions be necessary to make small meteorites?

    Even quite large meteors explode on reentry and become small meteorites. Collisions in space would be relatively rare... the distance between asteroids in the Asteroid belt is enormous... standing on one you probably would see any others... they are relatively small and too far apart.

    The Cheliyabinsk meteor for example was once material that formed inside a very large object and was formed in several km deep.

    Oh please... what high school did it go to and what was the name of the first girl it kissed?

    Gary with all due respect, but thats basic astronomy in french schools in 10th grade. What do you guys learn in New Zealand?

    Perhaps that is why there are so many French Astronomy experts...

    As for entry of earth atmosphere. Only a very thin layer gets heated in the way through the atmosphere. Its simply too quick. The so called fusion crust never exceed 2 or 3 mm.

    WOW... thanks for that explanation because I clearly didn't know that... my example of using a blow torch for a few seconds on a frozen turkey was way off... NOT.

    Im always happy ro lecture people from less fortunate countries, which cant afford high education.

    Yeah, that will help you win friends and impress girls... BTW which University did you attend...

    Dear god...i hate to teach elderly people...bigger rocks dont explode by the heat but because the aerodynamic forces. The rapid deccelartion starts to frakture the object by its way through atmosphere.

    And of course a genius like you understands that not every object entering the earths atmosphere is solid or rock... the object that exploded over Tunguska in 1908 was likely an iceball comet type object that shattered more than a dozen kms from the ground... when I say shattered I mean over 2,000 square kms of forest flattened and a glow in the night sky as far away as London... but no crater.

    Your link says exactly what i said. Aerodynamic forces, not heat breaks them apart.

    Well not really.... you make it sound like they all explode and all that ever hits the ground is little pieces... there are enough enormous craters still visible on earth to prove that to be wrong.


    Gary...you have no clue what you talk about. With all due respect, i demand a certain level of knowledge before i talk with someone over certain topics, you clearly dont meet the minimum criteria. Its ok. Im sure you had a lovely day. Did you go shopping? Family alright?
    Tsavo Lion
    Tsavo Lion

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    Chelyabinsk meteor Empty Re: Chelyabinsk meteor

    Post  Tsavo Lion on Thu Dec 05, 2019 6:22 am

    With all due respect, i demand a certain level of knowledge before i talk with someone over certain topics, you clearly dont meet the minimum criteria.
    Even if u r well versed in space rocks, many other topics we discussed showed ur own lack of knowledge, which makes me doubt ur level of expertise in anything.
    U seem to know best ur IQ level, how to boast about it, & show disrespect towards others.

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