How A Supernova Explodes (1985) [pdf]
astro.uconn.edu
astro.uconn.edu
Youtuber "But Why?" has a very nicely animated explanation of the current state of affairs of core-collapse supernovae at https://www.youtube.com/watch?v=Yt-SBT7nNfU
[0] Comment section of https://news.ycombinator.com/item?id=36362770
Your video perfectly complements the two others I love. I’d say the perfect watching order would be to first see the general supernova discussion by launch pad astronomy[1], followed by your suggestion, then the “how to build a black hole” by pbs space time [2].
But I am a biologist and I can assure you a good load of videos they make on it are at best not great explanations or at worst fundamentally unsubstantiated drivel. Like their latest one about how your body “kills cancers every day”. I went through their massive google doc “evidence” and as suspected not a single real reference to any proof that this is true. It COULD be true, but it’s not proven. I’m not even sure the evidence we have is actually pointing towards this direction. If it’s true that your immune system clears cancers every day, then immunosuppression should instantly plunge you into cancer. Does it? Not really. May be some blood cancers but that’s it.
Point is, they show shiny videos explaining almost plausible sounding scientific concepts. But often it’s still michio kaku level sensationalism. I personally believe this disingenuousness is the root cause of degradation in trust in science. The average person does have the ability to sniff bullshit and it eventually catches up to them in their mind that these scientists have no idea what they’re talking about (like my observation that these videos say there’s one neutron per proton in a supernova; I could instantly smell something rotten).
Unfortunately, these days it is close to rubbish.
Also, I’m pretty sure there’s no non-fake live stream of Betelgeuse on Youtube because it would require several robotic telescopes around the world programmed to coordinate and stream from wherever it’s a) night and b) Betelgeuse in the sky.
The study: https://arxiv.org/pdf/2306.00287.pdf
youtube explanation (Dr Becky Smethurst) https://www.youtube.com/watch?v=3QgLwpuDGhI&t=415s
The objections are primarily that the original paper assumes that a 2000 day period is the fundamental period of Betelguese's pulsation modes, which gives a radius that is much larger than what is observed in multiple wavelength bands.
It's unfortunate that Dr. Becky did not mention this in her video (perhaps it was published after she finished the script; even though it was out a while before the video was). I feel like this is not the first time that reputable science youtubers have jumped the gun on discussing research (Anton Petrov did something similar recently)
> doesn't have anything to do with the abnormal dimming in ~~2020~~ 2019 The Great Dimming is explained by this paper as being constructive interference of the pulsation modes (you can see this in their Figure 4. I don't know why Dr. Becky said this, but it doesn't seem to be correct.
Would be nice event to catch.
> Due to misunderstandings caused by the 2009 publication of the star's 15% contraction, apparently of its outer atmosphere, Betelgeuse has frequently been the subject of scare stories and rumors suggesting that it will explode within a year, and leading to exaggerated claims about the consequences of such an event. The timing and prevalence of these rumors have been linked to broader misconceptions of astronomy, particularly to doomsday predictions relating to the Mayan calendrical apocalypse. Betelgeuse is not likely to produce a gamma-ray burst and is not close enough for its X-rays, ultraviolet radiation, or ejected material to cause significant effects on Earth.
> Following the dimming of Betelgeuse in December 2019, reports appeared in the science and mainstream media that again included speculation that the star might be about to explode as a supernova – even in the face of scientific research that a supernova is not expected for perhaps 100,000 years. Some outlets reported the magnitude as faint as +1.3 as an unusual and interesting phenomenon, like Astronomy magazine, the National Geographic, and the Smithsonian.
> Phil Plait, in his Bad Astronomy blog, noting that Betelgeuse's recent behaviour, "[w]hile unusual . . . isn't unprecedented," argued that the star is not likely to explode "for a long, long time." Dennis Overbye of The New York Times agreed that an explosion was not imminent but added that "astronomers are having fun thinking about it.
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Evolutionary tracks for Betelgeuse https://arxiv.org/abs/1406.3143v2
> The best-fit MESA model left the main sequence about 10e6 yrs. ago, while for the EG model it was only about 3 × 10e5 years ago. Both models reached the base of the RGB about 40,000 years ago. We followed the star through the final ex- haustion of core helium burning in both codes, followed by brief epochs of core-carbon, neon, oxygen and silicon burning until core collapse and super-nova an age of 8.5 Myr since the ZAMS for the MESA code. Our best guess is that the star will supernova in less than ∼ 100, 000 yrs (even longer in the EG model). We note, however, that there error ellipse encompasses the entire track so that the star could be further along in its evolution. The constraint that it has passed the first dredge-up, however, means that the star is ascending the RSG phase. Our result is based upon mass loss from the base of the RGB is therefore a lower limit to how far it has evolved as a RSG.