Questions tagged [red-giant]
Questions about red giants, large luminous low-mass stars in a late phase of stellar evolution.
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Source of information on density profile of a red giant star?
Is there a good source of information of the expected density profile inside a red giant star?
I have read that when a star such as the sun has converted much or most of the hydrogen in its core into ...
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How can I calculate evolutionary timescales of low mass stars?
How can I calculate how long a star of a given mass will spend on an evolutionary branch before evolving off it?
I'm thinking about the evolution of low mass stars from the subgiant branch to the red ...
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Are there any binary red supergiants?
I wonder if we ever have identified or observed a pair of binary stars (red supergiants). And I also wonder what would happen if they exploded, (theoretically) as we haven’t observed it. Also, would ...
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What is the theoretical maximum variability a pulsating red giant can have such that a habitable planet can stay habitable for long periods of time?
I was reading about red giants and came across this statement:
Some research suggests that, during the evolution of a 1 M☉ star along the red-giant branch, it could harbor a habitable zone for ...
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Dynamics of red giant hydrogen shell
From what I understood from this answer to How can a red giant grow so big?
But this is not at all the way the shell fusing in a red giant self-regulates its fusion rate-- it cannot regulate its ...
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Jupiter/Saturn's fate after Sun goes red giant and planetary nebula?
The solar wind contributes a very small amount of matter to the gas giants. As the sun approaches the red giant phase, the solar wind increases significantly. 10% of the sun's mass lost as solar ...
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Why red giants have cooler surface than MS stars?
I know that with increasing age and depletion of hydrogen in the core the radiation inside a main sequence (MS) star increases pushing the envelope/surface of the star outwards. What I don't ...
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Is a star with 2/3 solar masses and 9/10 solar radii still in the main sequence?
As far as I know, K-type and G-type stars (among others) grow in radius as they age, eventually leading to red giant phases.
My question is, would a star that is about 0.66 solar masses and 0.94 solar ...
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Relation between initial mass and evolutionary phases lifetimes
Consider the following image (Source: An Introduction to Modern Astrophysics):
There seems to be a relation between the initial mass/mass at the beginning of the MS and the time spent during ...
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Could the Sun's planetary nebula be dangerous for the planets?
Since the Sun's mass isn't high enough it won't go supernova being a red giant but instead release a planetary nebula. So that seems to be kind of a substitute for a supernova. Would ejecting the ...
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