I have a bit of time on my hands, so let's do another 24h round of #AskAnAstrophysicist, but this time it's a thematic one.
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@glc xkcd always wins
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@vicgrinberg How bad has Starlink become to hinder professional examination of the stars from earth or does it all depend on the space telescopes now?
@Bugspriet @vicgrinberg I think that question can best be anwered by @sundogplanets
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I have a bit of time on my hands, so let's do another 24h round of #AskAnAstrophysicist, but this time it's a thematic one.
What do you want to ask an astrophysicist about stars? (I am a professional astrophysicist, part of whose work concerns itself with high mass stars & their winds and I've also taught a variety of astro university courses)
Boosts welcome. I may not be able to reply to all in case of many questions.
Oo, oo! I've got one!
If 'dark matter', whatever it is, interacts with other stuff by gravity, why do we seem not to have 'dark matter black holes'? And obvs, without any coherent theory of what 'dark matter' actually is, how would one know, or test the theory of how they behave or form?
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@vicgrinberg Maybe more of a physics question than a star question; if so, I apologize: what is your take on the new possibility that black holes may not contain singularities after all?
https://www.sciencenewstoday.org/no-more-singularity-physicists-propose-new-black-hole-paradigms
@secbox it's indeed not a star question. I discuss singularities as ideas eg in my book https://www.kosmos.de/de/schwarze-locher_1180792_9783440180792 - it would be too long for a post here.
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@vicgrinberg How much impact does dark matter have on stars? (Does the extra gravity influence internal processes, the number of CMEs, etc.) How much does it vary based upon the star's size? Is there the same relative regular matter to dark matter ratio regardless of size?
@clonezone none at all likely. Dark matter is distributed on much, much longer scales. It does play a major role in the formation of galaxies and thus, in a way, on the stars that will be later formed in them (no galaxies, no or very little stars), but to today's very detailed knowledge, it plays zero role in birth, life or death of individual stars.
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@vicgrinberg
This could be a question specific to stars (or even specific to massive stars) or it could be a question for all of astrophysics, I guess. Are we collecting data about the universe and its. contents faster than we (meaning you astrophysicists primarily) can analyze it? I know there are citizen science projects that help to classify galaxies and whatnot (Galaxy Zoo? I don't remember) but I imagine the flood of data far outstrips the ability of humans to parse it all. True? Are we getting ever further behind?@bkahn there is a lot of data, bit we are also pretty good at analysing it. The problem is more that there is a lot of additional stuff that can be learned from the same data (data collected to answer question A, can also be used for answer question B and, together with different data, possibly also C), but we don't have enough funding for professional astrophysicists to do the work.
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I have a bit of time on my hands, so let's do another 24h round of #AskAnAstrophysicist, but this time it's a thematic one.
What do you want to ask an astrophysicist about stars? (I am a professional astrophysicist, part of whose work concerns itself with high mass stars & their winds and I've also taught a variety of astro university courses)
Boosts welcome. I may not be able to reply to all in case of many questions.
@vicgrinberg which elements are made in which kind of stars and when during the Star lifetime?
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I have a bit of time on my hands, so let's do another 24h round of #AskAnAstrophysicist, but this time it's a thematic one.
What do you want to ask an astrophysicist about stars? (I am a professional astrophysicist, part of whose work concerns itself with high mass stars & their winds and I've also taught a variety of astro university courses)
Boosts welcome. I may not be able to reply to all in case of many questions.
@vicgrinberg
Any kind of exotic/theoretical star that science says could potentially exist but haven't been observed yet? -
@vicgrinberg which elements are made in which kind of stars and when during the Star lifetime?
@confusedMiddleAgedDad funnily, one of my very first scicomm pists on mastodon was on this https://mastodon.social/@vicgrinberg/109461953352960242 - for more info see the link in the image - here a nice article by the author herself
https://www.americanscientist.org/article/a-chemical-history-of-the-universe -
@vicgrinberg upper mass limit? Eddington limit still a thing? Deneb is my spirit star (Actually Vega, but that’s not high mass)
@glasspusher eddington limiy still a thing, yes
Upper mass limit depends on metallicity, so likely much more massive stars very early in the Universe. -
@echopapa it's the convection and the often fast rotation - both tend to tangle the magnetic fields more leading to a higher flare rate. Very close in exoplanets could also trigger flares, again via magnetic interaction https://www.skyatnightmagazine.com/space-science/exoplanets-close-cause-solar-flares
ah, thanks, fast rotation ist also a thing I haven't thought of.
Regarding rotation: I would guess in general very large stars have a long rotation period and the smaller the stars (or remnants like white dwarfs or pulsars) the rotation is getting faster and faster (due to conservation of momentum). Is this a general rule or are there types of stars with unusual behaviour? And ist differential rotation - like the sun - standard or are there stars with fusion processes which rotate like rigid body?
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@vicgrinberg
Any kind of exotic/theoretical star that science says could potentially exist but haven't been observed yet?@joxean Thorne-Zytkow objects come to mind, though they are not quiet normal stars : https://en.wikipedia.org/wiki/Thorne%E2%80%93%C5%BBytkow_object
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T tanyakaroli@expressional.social shared this topic
