Your videos are always so incredibly well made, well explained and simply so good. No other channel explains these topics with the simlicity you do. Props to you man! I look forward to the next installment.
Planetary nebula do have something to do with planets, because if red giant stars absorb their planets if the planets survive long enough they spin and move in side the star so it affects the shape of the planetary nebulas. 100% IQ
@@ItsJustAstronomical He loves everything! Especially how you explained the P-P and CNO. He loves the illustration, graphs, everything! :D He has been telling me about it for quite awhile. He loves everything space. :) Thank you so much for your replies! We are so glad we discovered your channel. :)
@@mitchjohnson4714 No, not really. The issue isn't that the charges are repelling one another. There's enough protons there to keep the charge electrically neutral. It really is a weird effect of quantum mechanics.
Sorry about that. I have all these interesting, but scary facts. I never know if I should share them. We might be able to get a spaceship ready in a billion years.
@@ItsJustAstronomicalwhat just for billion years of a human civilization to make that much advance only. So, it directly means that to reach type 2 or semi type 2 civilization, we need a whopping 2 BILLION YEARS 😮😮
My understanding is that 100 solar masses is roughly the upper limit for normal stars. Although the first stars in the early universe were different and had low metal and higher masses.
@@ItsJustAstronomical I think models place the limit at ~100 solar masses, but observations of the Tarantula Nebula have found candidate stars that are potentially 100 to 150-ish solar mass. Apparently, a dozen or so - with the caveat being that some of them may actually be close binaries.
Why don't slightly endothermic Ni(p,γ)Cu or Ni(α,γ)Zn processes happen in heavy stars anytime during Si burn but before core collapse begins? Assume stellar core has gravitational energy to spend, there is more than enough energy to convert significant portion of Fe/Ni core into Cu/Zn. Why this does not happen ? Skip talking abut: - stellar evolution - supernovae - s-,r- processes - Cu & Zn real origin, skip Discovery channel talk, focus on the topic at hand. University level explanation is expected, that uses binding energy, photodissociation rates, Saha equation, nuclear statistical equilibrium e.t.c The core might initially be either degenerate or non-degenerate, address both states.
I don't know. I'm not an expert on this topic. I made this video because I couldn't find good videos on this subject. Based on your question I think you may know more about this subject than me. I've actually been trying to find experts on this subject to help me out.
@@ItsJustAstronomical I hope that an expert may eventually stumble upon one of my questions like this that I have diligently placed under videos that mention the Silicon burn phase.
@@phdnk *"Why don't slightly endothermic Ni(p,γ)Cu or Ni(α,γ)Zn processes"* Actually these 2 processes are EXOTHERMIC. And the alpha ladder is exothermic all the way up to tin: C12+He4→O16(+7.16MeV) O16+He4→Ne20(+4.73MeV) Ne20+He4→Mg24(+9.32MeV) Mg24+He4→Si28(+9.98MeV) Si28+He4→S32(+6.95MeV) S32+He4→Ar36(+6.64MeV) Ar36+He4→Ca40(+7.04MeV) Ca40+He4→Ti44(+5.13MeV) Ti44+He4→Cr48(+7.70MeV) Cr48+He4→Fe52(+7.94MeV) Fe52+He4→Ni56(+8.00MeV) Ni56+He4→Zn60(+2.70MeV) Zn60+He4→Ge64(+2.58MeV) Ge66+He4→Se68(+2.29MeV) Se68+He4→Kr72(+2.15MeV) Kr72+He4→Sr76(+2.72MeV) Sr76+He4→Zr80(+3.69MeV) Zr80+He4→Mo84(+2.71MeV) Mo84+He4→Ru88(+2.26MeV) Ru88+He4→Pd92(+2.27MeV) Pd92+He4→Cd96(+3.03MeV) Cd96+He4→Sn100(+3.10MeV) Sn100+He4→Te104(-5.49MeV) *"Assume stellar core has gravitational energy to spend, there is more than enough energy to convert significant portion of Fe/Ni core into Cu/Zn. Why this does not happen ?"* i will try to give an explanation. My explanation is not even close to university level. At silicon burning, nuclei photolyze and combine again, eventually achieving nuclear statistical equilibrium. For nuclei heavier than nickel the alpha capture gets much less exothermic, meaning that the reverse reaction(photolysis) takes less energy to happen, so they are mostly photolyzed down to nickel. And at equal numbers of protons and neutrons Ni56 is the nuclei with the highest binding energy, due to that it ends up as the MAJOR product, MINOR amounts of other nuclei such as Zn60, Cu58, Fe52, Co54 and others will still be present.
These videos are too informative to challenge other educational institutions so they cannot make this type of nutshell brief videos and instead they will make their long boring a$$ 8 hr long lectures sessions just to make their per hour each money costing btw 40,000 USD to 100,000 USD as an average.
I should have been more clear that I was just illustrating a point here not showing real data. HR diagrams are the main source of evidence. From comparing different clusters at different ages we can see how stars evolve over time and this agrees with the simulations.
Just as I'm about to take an exam in advanced stellar evolution, I see this video on the homepage: couldn't hope for a better timing! Wonderful and precise explanation, can't wait for the next one!
Sounds like an interesting class. I've actually never taken a class like that, I've just been reading a lot of books. I hope I got everything right. Good luck on the exam!
@@ItsJustAstronomical Sounds interesting, do you have any good book recommandations about stars or astronomy in general? I am very interested in expending my knowledge on the topic
@@Paul1_snd.art.s Here are the books I used to make my videos about stars. Some of these books are quite dense. I recommend starting with the first book. Stellar Evolution and Nucleosynthesis by Ryan and Norton Stellar Interiors by Hansen, Kawaler, and Trimble Stars and Stellar Evolution by De Boer and Seggewiss Stellar Structure and Evolution by Kippenhahn, Weigert, and Weiss For a much lighter general history of astronomy I'd recommend: Coming of Age in the Milky Way
Your videos are always so incredibly well made, well explained and simply so good. No other channel explains these topics with the simlicity you do. Props to you man! I look forward to the next installment.
Planetary nebula do have something to do with planets, because if red giant stars absorb their planets if the planets survive long enough they spin and move in side the star so it affects the shape of the planetary nebulas. 100% IQ
When will be the release of the How Stars Die video? My little one is waiting for it. Thank you!
I think I'll finish it within a week. I've been traveling and distracted by other things. I now finally have time to finish it.
@@ItsJustAstronomical thank you so much! He is excited (he's 6 btw 😆). Love your videos!
@@AkiDreams Oh, that warms my heart! I feel honored to have a young fan, especially considering the difficulty of the subject matter.
@@ItsJustAstronomical He loves everything! Especially how you explained the P-P and CNO. He loves the illustration, graphs, everything! :D He has been telling me about it for quite awhile. He loves everything space. :)
Thank you so much for your replies! We are so glad we discovered your channel. :)
Nice. I keep trying to understand the helium flash, and couldn't get it. Now i know i need to learn more about quantum physics
Yeah, there's no getting around it. Degenerate matter is weird.
@@ItsJustAstronomical Is degeneracy pressure at a more macro-scale the same as electrostatic "pressure" or force?
@@mitchjohnson4714 No, not really. The issue isn't that the charges are repelling one another. There's enough protons there to keep the charge electrically neutral. It really is a weird effect of quantum mechanics.
What do you think about the recent discovery of "old smoker" stars?
It seems quite interesting, although I can't say I know a lot about them.
@@ItsJustAstronomical I mean, I'm pretty sure most people know very little about them - they were discovered only last year really
Now I have one more thing to worry about.
Sorry about that. I have all these interesting, but scary facts. I never know if I should share them. We might be able to get a spaceship ready in a billion years.
@@ItsJustAstronomicalwhat just for billion years of a human civilization to make that much advance only. So, it directly means that to reach type 2 or semi type 2 civilization, we need a whopping 2 BILLION YEARS 😮😮
❤❤
There aren't any any stars above 100 solar masses? Are you sure about that?
My understanding is that 100 solar masses is roughly the upper limit for normal stars. Although the first stars in the early universe were different and had low metal and higher masses.
@@ItsJustAstronomical I think models place the limit at ~100 solar masses, but observations of the Tarantula Nebula have found candidate stars that are potentially 100 to 150-ish solar mass. Apparently, a dozen or so - with the caveat being that some of them may actually be close binaries.
Interesting, I probably oversimplified things.
Why don't slightly endothermic Ni(p,γ)Cu or Ni(α,γ)Zn processes happen in heavy stars anytime during Si burn but before core collapse begins?
Assume stellar core has gravitational energy to spend, there is more than enough energy to convert significant portion of Fe/Ni core into Cu/Zn. Why this does not happen ?
Skip talking abut:
- stellar evolution
- supernovae
- s-,r- processes
- Cu & Zn real origin,
skip Discovery channel talk, focus on the topic at hand.
University level explanation is expected, that uses binding energy, photodissociation rates, Saha equation, nuclear statistical equilibrium e.t.c
The core might initially be either degenerate or non-degenerate, address both states.
I don't know. I'm not an expert on this topic. I made this video because I couldn't find good videos on this subject. Based on your question I think you may know more about this subject than me. I've actually been trying to find experts on this subject to help me out.
@@ItsJustAstronomical I hope that an expert may eventually stumble upon one of my questions like this that I have diligently placed under videos that mention the Silicon burn phase.
@@phdnk *"Why don't slightly endothermic Ni(p,γ)Cu or Ni(α,γ)Zn processes"*
Actually these 2 processes are EXOTHERMIC.
And the alpha ladder is exothermic all the way up to tin:
C12+He4→O16(+7.16MeV)
O16+He4→Ne20(+4.73MeV)
Ne20+He4→Mg24(+9.32MeV)
Mg24+He4→Si28(+9.98MeV)
Si28+He4→S32(+6.95MeV)
S32+He4→Ar36(+6.64MeV)
Ar36+He4→Ca40(+7.04MeV)
Ca40+He4→Ti44(+5.13MeV)
Ti44+He4→Cr48(+7.70MeV)
Cr48+He4→Fe52(+7.94MeV)
Fe52+He4→Ni56(+8.00MeV)
Ni56+He4→Zn60(+2.70MeV)
Zn60+He4→Ge64(+2.58MeV)
Ge66+He4→Se68(+2.29MeV)
Se68+He4→Kr72(+2.15MeV)
Kr72+He4→Sr76(+2.72MeV)
Sr76+He4→Zr80(+3.69MeV)
Zr80+He4→Mo84(+2.71MeV)
Mo84+He4→Ru88(+2.26MeV)
Ru88+He4→Pd92(+2.27MeV)
Pd92+He4→Cd96(+3.03MeV)
Cd96+He4→Sn100(+3.10MeV)
Sn100+He4→Te104(-5.49MeV)
*"Assume stellar core has gravitational energy to spend, there is more than enough energy to convert significant portion of Fe/Ni core into Cu/Zn. Why this does not happen ?"*
i will try to give an explanation.
My explanation is not even close to university level.
At silicon burning, nuclei photolyze and combine again, eventually achieving nuclear statistical equilibrium.
For nuclei heavier than nickel the alpha capture gets much less exothermic, meaning that the reverse reaction(photolysis) takes less energy to happen, so they are mostly photolyzed down to nickel. And at equal numbers of protons and neutrons Ni56 is the nuclei with the highest binding energy, due to that it ends up as the MAJOR product, MINOR amounts of other nuclei such as Zn60, Cu58, Fe52, Co54 and others will still be present.
First
It's amazing how much detail you can cram into these videos that I never learned in school
When our star grows old we’re toast
Literally, actually we’re gonna be atomized Skip burning we’re gonna ionize, and so will earth
why these kind of videos not seen everywhere man😢
These videos are too informative to challenge other educational institutions so they cannot make this type of nutshell brief videos and instead they will make their long boring a$$ 8 hr long lectures sessions just to make their per hour each money costing btw 40,000 USD to 100,000 USD as an average.
The reason I think stars go red, giant, is because the core gets so dense that it expels matter away from it is born
The Simulated image at 2:20 looks so similar to the actual observations that it is highly suspicious.
I should have been more clear that I was just illustrating a point here not showing real data. HR diagrams are the main source of evidence. From comparing different clusters at different ages we can see how stars evolve over time and this agrees with the simulations.
Does ideal gas law hold for stars?
It's pretty accurate if the star is not degenerate.
Just as I'm about to take an exam in advanced stellar evolution, I see this video on the homepage: couldn't hope for a better timing! Wonderful and precise explanation, can't wait for the next one!
Sounds like an interesting class. I've actually never taken a class like that, I've just been reading a lot of books. I hope I got everything right. Good luck on the exam!
@@ItsJustAstronomical Sounds interesting, do you have any good book recommandations about stars or astronomy in general? I am very interested in expending my knowledge on the topic
@@Paul1_snd.art.s Here are the books I used to make my videos about stars. Some of these books are quite dense. I recommend starting with the first book.
Stellar Evolution and Nucleosynthesis by Ryan and Norton
Stellar Interiors by Hansen, Kawaler, and Trimble
Stars and Stellar Evolution by De Boer and Seggewiss
Stellar Structure and Evolution by Kippenhahn, Weigert, and Weiss
For a much lighter general history of astronomy I'd recommend:
Coming of Age in the Milky Way
@@ItsJustAstronomical Thank you so much!!
I'm going to check them out!