Stellar Evolution, Supernovae and the Fate of the Sun

[@Stanman121]

My gosh. I am so glad I found this channel. It is the best on KZbin. Not kidding. Yes I love anything Cosmos and Physics but I also love 80s Nostalgia, toys, hiking, nature, history... This channel here. Tops them all. Jason is awesome. Thank you. Best wishes from sunny South-Africa today

[@JasonKendallAstronomer]

That's awesome to hear! I'm glad you're enjoying the content. And thanks for being a member!

[@rosco0567]

Fascinating and educational. Awesome content for bedtime. Thanks. Just going through back catalogue. 🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@JasonKendallAstronomer]

Glad you enjoyed it!

[@pavelssuskis3468]

Finally! Informative and interesting channel about astrophysics in English! Most of the channels I saw, that are that good are in Russian

[@JasonKendallAstronomer]

Thanks!

[@pavelssuskis3468]

@@JasonKendallAstronomer To be honest this is a rare example of good infotainment. I just got tired of those nice-pictured short videos or kinda Discovery videos that have no formulae. Which is a key for understanding what happens and why!

[@dhjerth]

19:30 I'm having a really hard time wrapping my head around this bit with helium poisoning and ensuing expansion. Excuse my cluelessness as I'll try to explain what I understand: Helium builds up, hydrogen runs low, this causes gravitation to overcome "outward pressure", heating up the core/leading to some helium degeneracy. The helium is still "inert" wrt fusion. Remaining hydrogen is pushed into a shell around the core and still undergoes fusion, preventing collapse. The surface temperature drops. And now is when I'm lost: the sun starts growing in size. Why would it grow in size? Unless some new exothermic stuff starts happening, shouldn't the sun be shrinking? I watched another video on this, it might actually have been from this same channel, (EDIT: actually it was probably this video, just a minute later around 22:00) that explained the swelling by hydrogen needing to expand in order to keep fusing, because there is less of it, and so it has to sort of "speed up" in order to find other hydrogens to fuse with. I must be wrong because this all sounds completely teleological to me! If gravitational pressure overcomes "heat expansion" (again please excuse my awful terminology), how could that lead to more expansion? Does it have anything to do with energy/heat distribution across the layers? Does hot plasma expand like hot gas does? Or is the explanation complete at the referenced timestamp 19:30 and I'm just not understanding it? I would be most thankful for any pointers, and thank you for these wonderful lectures.

[@basfinnis]

Always a pleasure to listen to. Jason was the first person to help me understand what actually happens in a supernova. Wonderful stuff. Thank you 😉

[@Palochii]

Your videos are incredible! I found you because of a university work I was doing but now I keep watching after it's over lol Thank you for sharing your knowledge

[@JasonKendallAstronomer]

I'm glad you're enjoying them!

[@Choofalong]

LOVE your long forms. Looking forward to a recap. Seen your original Video and am a fan

[@paigemcloughlin4905]

Watching in the wee hours tonight.

[@trevorvanbremen4718]

Three and a half hours??? OMG Jason!!! It looks like it's gonna be a l-o-n-g night for me tonight! (Hopefully, there will be a lot of stuff you've already covered in _other_ videos that I can FF through!)

[@climbeverest]

Incredible

[@movax20h]

Oof. What a fantastic video. Was nice to refresh a lot of knowledge from university, but also learn things I didn't read about in the books or during astrophysics lectures. I didn't know about the helium flash pulsing, or the carbon dredging process due to convection and mixing. Really interesting. Also, out of curiosity, in the current sun with He inner core growing, is it really pure He, or is there some minuscule probability of higher elements forming in trace quantities? I guess, based on the fact that triple-alpha process is highly non-linear, that at 15MK, it is essentially non-essential, and we might be talking like trace quantities of C, N forming maybe. Was wondering what amount would that be. Found your channels yesterday, as I was browsing some other stuff, including stuff on recent supernova simulations, and stuff. But glad I found it.

[@scottdorfler2551]

I have to disagree with your take on M class Red Dwarfs. A star that stays on its main sequence for a trillion years is anything but boring.

[@JasonKendallAstronomer]

Can't really argue with that.

[@papuetressbaribas355]

I wonder where is the remnant of the supernova that made possible for our solar system to form, how many lightyears across ? How many neighbor stars formed from that supernova? I have so many questions :) I really enjoy this videos and your way of explaining things, keep up the good work!

[@Jono4174]

2:20:12 shouldn’t one of the third or fourth interactions be an anti neutrino? Also the second interaction is also wrong.

[@kellychuba]

You are a national treasure. I really want to see your exams, is that weird?

[@JasonKendallAstronomer]

A little, but interesting, nonetheless. Perhaps a video where I go through one of my WPU final exams?

[@dt5072]

Thanks mr kendall been with your channel for a few years and always good.more ai crap than ever these days

[@swainscheps]

Like red dwarfs…(dwarves?) is it possible there are many many undetected brown solar systems out there? With a brown dwarf at the center of some very cold solar systems? Kinda sad to think about them all actually…

[@mikefisher5005]

How did supernova 1987 neutrinos get here 2 hours before the light?

[@movax20h]

SN1987A was a core collapse supernova. Neutrinos are formed during the core collapse, in seconds, but the star before that was probably 5AU in radius. It takes hours for the shockwave to reach the photosphere, even at 1/3 of the speed light.

[@mikefisher5005]

How can 1 supernova ourshine a galaxy?

[@Solnoric]

@@mikefisher5005 it's an absolutely insane amount of energy.