Questions tagged [photosphere]
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Do stars become more metal-rich as they evolve?
Since we determine the metallicity of a star ([Fe/H] or Z) from surface emission, does this change as it ages? For instance, can a young star with a measured [Fe/H] of -0.02 have a higher value when ...
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What does this "web on the surface of the Sun" image reflect? What does 789 nm show us?
What is this web on the surface of the Sun? has got me thinking.
This is probably not a normal color photo.
The cooler areas are really dark!
update: Comments point out
The NSO press release says ...
- 31.1k
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Wilson effect: How "deep" are sunspots?
I recently learned about the Wilson effect of the Sun's atmosphere. The 2009 Saas Fee Advanced Course 39 states:
Near the solar limb, the umbra [the circular dark region of a sunspot] and the centre-...
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What effect does stellar granulation to have on a chemical analysis of a star's spectrum?
The spectrum from stellar granules will obviously be for hotter gas, while the spectrum from the lanes between them will be for cooler gas.
Does this "average out" so that an average ...
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At what depth below the Sun's surface does the density reach that of water?
I'd like to write a short supplementary answer to A probe floating in Sun's surface but in order to do so I need to know at roughly what depth relative to the Sun's surface the mass density reaches 1 ...
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Are any supergiants translucent?
Are any supergiants translucent? Some have volumes thousands of times more than the Sun's while having maybe twenty times the mass of the Sun which makes them sound rather diffuse. If there was a very ...
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Distance between "inside" and "outside" of the sun?
In a solar eclipse, and from our distance, the sun's surface appears to be pretty much exactly that, a surface. However, the reality of it's being an extremely tenuous plasma makes things very much ...
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What class of elements are providing the many electrons needed to make the H- ion?
Continuous absorption by the H- ion reaches its maximum in the cool atmospheric layers of G stars. At these temperatures, most of the hydrogen atoms are neutral; but what class of elements is ...
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Do neutron stars have something like a gamma-ray photosphere? Are gamma rays from below it limited more by the nuclei or electrons?
@RobJeffries' answer to Is there evidence of super-heavy elements in the x-ray and gamma-ray spectrums of neutron stars? includes the sentence:
However, the only things that contribute to a neutron ...
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Density of a sunspot compared to the surrounding photosphere?
Is the density of a sunspot different by more than a factor of ten compared to the area surrounding the sunspot?
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What is the density profile within the Sun's photosphere? Which one of these is wrong?
The Sun's photosphere contains the Sun's surface as defined by opacity = 2/3 point. I'd like to see the profile of mass density from bottom to top of the photosphere. I did a quick search and got ...
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