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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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.
What are some of the biggest unanswered questions about stars? What don't you know about stars that you wish you did? And might some of these questions be answered in the future with better equipment/technology/computing power?
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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@mastodon.social So to my knowledge stars tend to emit different visible and invisible wavelengths depending on a variety of factors. Our telescopes tend to focus on a given range of the full spectrum depending on their design, as a necessity of visualization and engineering.
My question is, are there any stars that we've studied in-depth enough to understand / visualize their complete spectral output, or is our data not that complete yet? -
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
Is Johnny Depp nice in person? -
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 say you have a sci-fi spaceship that you can manipulate the propulsion from to take flight from the surface of a planet, at 1 m/s … because we live forever or something
What happens when the futuristic superforce of the motor pushing you at 1 m/s doesn’t come closer than that to escape velocity?
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What are some of the biggest unanswered questions about stars? What don't you know about stars that you wish you did? And might some of these questions be answered in the future with better equipment/technology/computing power?
@bkahn oh, there are still so many! I'll pick one I especially like: we do not understand the most massive stars that existed very early in the universe, when there were few heavier elements super well. Somehow, in their death, these stars have managed to create black holes that are just so bigger than we would have expectes - but we do have ideas what may be the cause, so we are working hard on finding out which one is correct.
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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 I recently saw an interview clip of the Artemis II crew, and I think either Reid or Victor said that something that surprised them was the “three-dimensionality” of space — that the stars appear more 3-D out there than they do when seen from Earth. Do you think you could expand on that? I’m having a hard time visualizing how much more “3-D” a field of distant points of light could look. Is it that the parallax effect on stars was more noticeable at their speed?
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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 i have a rather metaphysical question that has been torturing me a while. What's the purpose of doing all this great science out there in space, when we are just destroying our very own and only spaceship at the same time?
I am really struggling to find sense in my plasma phenomena thesis given the state of the world.
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@vicgrinberg@mastodon.social So to my knowledge stars tend to emit different visible and invisible wavelengths depending on a variety of factors. Our telescopes tend to focus on a given range of the full spectrum depending on their design, as a necessity of visualization and engineering.
My question is, are there any stars that we've studied in-depth enough to understand / visualize their complete spectral output, or is our data not that complete yet?@celestiallavendar we do have a pretty good prediction for the overall shape of the emission of stars (they pretty much radiate as any body of a given temperature would, with well defined amounts of radiation in different wavelength bands) and we've got a lot of what we call "multiwavelength" coverage of many different stars. It doesn't mean that we are done, though - telescopes cover not only different wavelength ranges, but also have different resolution and there is more info in there.
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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.
My understanding is that heavy elements were formed by super novas, and also that super novas are rare occurrences. How do these two facts(?) square up, given that we have a fair amount of them in Earth's crust?
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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 So what happens to all the "metals" that fall into a star? "Metals" being anything heavier than H and He. That stuff, at least some of it, makes its way down to the core. Until the core gets hot and pressurized enough to fuse that stuff, it's just a drag on fusion. Could a star be poisoned enough to choke out the fusion process altogether?
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@vicgrinberg i have a rather metaphysical question that has been torturing me a while. What's the purpose of doing all this great science out there in space, when we are just destroying our very own and only spaceship at the same time?
I am really struggling to find sense in my plasma phenomena thesis given the state of the world.
@Nephele to me, doing science is like doing art, it's deeply human. The first humans pressed their ocher red hands onto walls of caves and it still touches me. The same way science and trying to understand the world touches something deep in the human soul. When we stop doing art and trying to understand the world (so doing science), we stop being human.
And *hugs* it's hard times...
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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 what would happen to your arm if you raised it while the lightspeed is 0?
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@celestiallavendar we do have a pretty good prediction for the overall shape of the emission of stars (they pretty much radiate as any body of a given temperature would, with well defined amounts of radiation in different wavelength bands) and we've got a lot of what we call "multiwavelength" coverage of many different stars. It doesn't mean that we are done, though - telescopes cover not only different wavelength ranges, but also have different resolution and there is more info in there.
@vicgrinberg@mastodon.social I'll have to check out the multiwavelength coverage, that sounds very interesting. The fact that so much of what's out there we can't truly see constantly fascinates me, so I appreciate your answer!
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@vicgrinberg I recently saw an interview clip of the Artemis II crew, and I think either Reid or Victor said that something that surprised them was the “three-dimensionality” of space — that the stars appear more 3-D out there than they do when seen from Earth. Do you think you could expand on that? I’m having a hard time visualizing how much more “3-D” a field of distant points of light could look. Is it that the parallax effect on stars was more noticeable at their speed?
@bluejay I have no idea what the Artemis crew meant since I've never been to space or seen the interview. Parallax needs you to make measurements on two very far away locations. And depth perception does not work on high distances. What I imagine is that stars don't twinkle in space - twinkling comes from the atmosphere, so the view must be more clear and thus our brains plays interesting games with us interpreting this!
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@vicgrinberg@mastodon.social I'll have to check out the multiwavelength coverage, that sounds very interesting. The fact that so much of what's out there we can't truly see constantly fascinates me, so I appreciate your answer!
@celestiallavendar I feel the same! This (or a variation thereof) https://asd.gsfc.nasa.gov/archive/mwmw/mmw_images.html is still one of my favorite images ever!
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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.
a question not directly connected to stars (but concerning mass in our universe):
Currently we "need" a lot of dark matter and dark energy to keep our universe models "running", but still have few ideas about both dark things and how to verify the various theories (WIMPs, axions, etc.).
Do you think we will find some day this type of matter and energy or do you think the answer is more lying in the area of MOND (modified Newtonian dynamics), TeVes, entropic gravity, so that some "constants" in the universe are not so constant as we think?
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@vicgrinberg So what happens to all the "metals" that fall into a star? "Metals" being anything heavier than H and He. That stuff, at least some of it, makes its way down to the core. Until the core gets hot and pressurized enough to fuse that stuff, it's just a drag on fusion. Could a star be poisoned enough to choke out the fusion process altogether?
@GranVegas actually, the metals (and thanks for using the astrophysical meaning of it, otherwise I always have to explain our strange terminology
) don't fall into the core - stars are pretty well mixed! And currently, we have still very, very little metals around.I guess if one were to start with a metal only cloud, one could possibly directly form a (cold) white dwarf, but that's a speculation and as said, we still have very little metals.
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@bluejay I have no idea what the Artemis crew meant since I've never been to space or seen the interview. Parallax needs you to make measurements on two very far away locations. And depth perception does not work on high distances. What I imagine is that stars don't twinkle in space - twinkling comes from the atmosphere, so the view must be more clear and thus our brains plays interesting games with us interpreting this!
@vicgrinberg Thanks! I found a link to the clip, if you can access it; it’s actually Jeremy Hansen making the observation, near the start of the video.
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a question not directly connected to stars (but concerning mass in our universe):
Currently we "need" a lot of dark matter and dark energy to keep our universe models "running", but still have few ideas about both dark things and how to verify the various theories (WIMPs, axions, etc.).
Do you think we will find some day this type of matter and energy or do you think the answer is more lying in the area of MOND (modified Newtonian dynamics), TeVes, entropic gravity, so that some "constants" in the universe are not so constant as we think?
@echopapa sorry, as said, I'd like this one to be focussed on the stars topic
But re: dark matter & dark energy - keep an eye out on upcoming Euclid @ec_euclid results, I expect a lot of cool stuff in the next years. Also I heard the new book on "Dunkle Materie" (Beck Wissen) by @sianderl is very good, but haven't read it yet. -
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 bearing in mind the two items I have heard/seen, viz.
1. There is a wave which is not captured by known black holes; and
2. That particle acceleration within our measurable frame is below that which would escape an event horizon, meaning we may be inside a black hole;What evidence is there for entropy to be incontestable?
