Crystallized White Dwarfs

[hazelm]

https://www.sciencedaily.com/releases/2019/01/190109142631.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Ftop_news%2Ftop_science+%28ScienceDaily%3A+Top+Science+News%29

 

The process had been predicted.  Now it has been observed.  Evidence has been found that white dwarf stars - which are used as cosmic clocks - tend to crystallize as they cool. 

[exchemist]

https://www.sciencedaily.com/releases/2019/01/190109142631.htm?utm_source=feedburner&utm_medium=email&utm_campaign=Feed%3A+sciencedaily%2Ftop_news%2Ftop_science+%28ScienceDaily%3A+Top+Science+News%29

 

The process had been predicted.  Now it has been observed.  Evidence has been found that white dwarf stars - which are used as cosmic clocks - tend to crystallize as they cool. 

Nice! 

 

The real point here seems to be the progressive release of latent heat, while the phase change takes place, over millions of years. This would be expected to halt the normal cooling down process that one would otherwise expect, while all this extra chemical energy is released. Just as water being cooled sticks at 0C until it has all converted to ice and only then carries on cooling further.  

 

This accounts rather nicely for why they observe so many white dwarfs (dwarves?) all apparently "stuck" at the same temperature. 

Edited January 10, 2019 by exchemist

[hazelm]

Nice! 

 

The real point here seems to be the progressive release of latent heat, while the phase change takes place, over millions of years. This would be expected to halt the normal cooling down process that one would otherwise expect, while all this extra chemical energy is released. Just as water being cooled sticks at 0C until it has all converted to ice and only then carries on cooling further.  

 

This accounts rather nicely for why they observe so many white dwarfs (dwarves?) all apparently "stuck" at the same temperature.

Fascinating, too, because I always think of stars as gas and ( thinking wrongly ) can't freeze/solidify.  Of course it can. Steam does.  I'd love to see the crystals close up.  Wonder if they all look the same.  (It's the artist in me.)  Truthfully,  I don't think I am getting the full picture from that article.  Nice to think about anyway.

[exchemist]

Would it be all that highly compressed carbon you are thinking of. After all diamonds are a girls best friend :) Especially really big ones

I was wondering what state of matter these "crystals" (in journalese) would actually be in. After all, a white dwarf is supposed to so dense that the electrons are squeezed out of the atoms, so you would have only bare nuclei, or atomic cores at least, in arrays, with an electron "gas" forming the "atmosphere". Sounds like Hades.

 

I think I'd forget crystals as such. What they mean is a phase change leading to a lower energy state, such that latent heat is released, holding up the cooling process. I rather doubt anyone has much real idea of how to model the phase change involved. 

[hazelm]

Would it be all that highly compressed carbon you are thinking of. After all diamonds are a girls best friend :) Especially really big ones

Now, you have raised a question.  But I think the answer is no.  That crystallization can't be the production of gemstones because this is the first observation.  Still ---- our previous observations of gemstones have been on Earth, not in dying suns. 

 

Diamonds?  No.  I prefer rubies.  Love that deep  red.  Emeralds are nice, too, but they don't match up to rubies.  :-)

 

Back to the beginning, I was really thinking of metals like iron.  Isn't the origin of those in stars?  Heavy metals as elements.

[exchemist]

Now, you have raised a question.  But I think the answer is no.  That crystallization can't be the production of gemstones because this is the first observation.  Still ---- our previous observations of gemstones have been on Earth, not in dying suns. 

 

Diamonds?  No.  I prefer rubies.  Love that deep  red.  Emeralds are nice, too, but they don't match up to rubies.  :-)

 

Back to the beginning, I was really thinking of metals like iron.  Isn't the origin of those in stars?  Heavy metals as elements.

crossed with my post Hazel and you are right to forget gemstones.

 

The origin of ALL the elements heavier than H, He and Li is in stars, by nuclear fusion reactions. We are all made of the "ash" of stars, indeed.

 

As the priest says on Ash Wednesday, making the Sign of the Cross on your forehead with ash  (from burnt palms left over from the previous Palm Sunday): "Remember, Man, thou art but dust, and unto dust thou shalt return."

Edited January 10, 2019 by exchemist

[hazelm]

I was wondering what state of matter these "crystals" (in journalese) would actually be in. After all, a white dwarf is supposed to so dense that the electrons are squeezed out of the atoms, so you would have only bare nuclei, or atomic cores at least, in arrays, with an electron "gas" forming the "atmosphere". Sounds like Hades.

 

I think I'd forget crystals as such. What they mean is a phase change leading to a lower energy state, such that latent heat is released, holding up the cooling process. I rather doubt anyone has much real idea of how to model the phase change involved. 

Isn't there another time when electrons escape atoms and - I think - become ions.  I read about those ages ago but don't think they were part of this dwarfs story.  Then Bill Bryson has something in his book.  He was wondering why electrons didn't fall back to a lower level. 

 

I need to re-read all this.  Too much to remember.    Of course, in this case from Warwick, they had predicted that this existed fifty years ago, just had not actually observed it.  So, maybe some of us confused prediction with fact. 

 

"phase change".  Makes sense.  A good phrase for it. 

[exchemist]

Isn't there another time when electrons escape atoms and - I think - become ions.  I read about those ages ago but don't think they were part of this dwarfs story.  Then Bill Bryson has something in his book.  He was wondering why electrons didn't fall back to a lower level. 

 

I need to re-read all this.  Too much to remember.    Of course, in this case from Warwick, they had predicted that this existed fifty years ago, just had not actually observed it.  So, maybe some of us confused prediction with fact. 

 

"phase change".  Makes sense.  A good phrase for it. 

Hard to say without more context. In a plasma you have ions and free electrons, because it is so hot that the thermal energy of the ions hitting each each other is enough to knock electrons out of atoms. So they drop back but get kicked out again. Could it be that? 

[hazelm]

Hard to say without more context. In a plasma you have ions and free electrons, because it is so hot that the thermal energy of the ions hitting each each other is enough to knock electrons out of atoms. So they drop back but get kicked out again. Could it be that? 

I don't know.  The ones I read about so long ago have another purpose once they escape the original atom.  I'll think on it.

[hazelm]

hydrogen ions!  That's what it was about.  Google has this on its links:  "Hydrogen ion. A hydrogen ion is formed when a hydrogen atom loses an electron and therefore becomes positively charged (it has a charge of +1). A hydrogen atom is therefore often referred to as just a proton, as it is left with only one proton and no electrons, as a H atom only has one of each.Oct 18, 2018." 

 

Now what happens to the "lost" electron?  There was more to the story.  I'll probably think of it about 2:00 AM.  I know it doesn't stay free for long.  Until manana.