Questions tagged [stellar-atmospheres]
Atmospheres of stars and star-like objects. For atmospheres of planets, moons, and other solar system bodies excluding stars, use "planetary-atmosphere" instead.
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What causes the Balmer Jump?
To quote Wikipedia:
Balmer Jump is caused by electrons being completely ionized directly from the second energy level of a hydrogen atom (bound-free absorption), which creates a continuum absorption ...
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Can we use atmospheric retrieval techniques on stars?
Although there are lots of examples of atmospheric retrieval techniques being used on exoplanets, and recently brown dwarfs, I can't find any mention of atmospheric retrieval techniques being used on ...
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Is the gas in a planet forming disk around a star comparable in density to an atmosphere?
If you were standing on a planetesimal in the planet forming disk of a new solar system (or our own, billions of years ago), would you be able to feel "interplanetary wind"? Would it be ...
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At what point does an astronomical body's surface stop being gas giant-like and start being sun-like?
I've generally seen brown dwarfs depicted as more massive and slightly wider Jupiters in varying colors with banded cloud structures, sometimes hot enough to be visible glowing. I've also seen red ...
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Is there molecular hydrogen in the Sun's atmosphere? If so, how much, and how was that first determined and measured?
I don't have a license to practice chemistry, but I'll convert Wikipedia's bond dissociation energy of 435.7 kJ/mol to eV by dividing it by $C / N_A$ where $C$ is 1 Coulomb and $N_A$ is Avogadro's ...
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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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The sun "burns" hydrogen and even has "campfires" on it, but has anyone calculated a rate of actual chemical burning on the Sun?
Answers to Hydrogen burning vs Hydrogen fusing explain that in astrophysics "burning" generally refers to nuclear fusion or at least nuclear reactions1, and information at
Why didn't we ...
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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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Help understanding ring diagram analysis used in helioseismology
I need help understanding something. In global helioseismology we study the modes directly (stationary waves characterized by 3 integers numbers: $n$, $l$ and $m$). As the angular degree $l$ becomes ...
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Would the electron cyclotron-maser emission mechanism affect Proxima b's ability to retain an atmosphere?
In a recent arXiv preprint, Pérez-Torres et al. "Monitoring the radio emission of Proxima Centauri" claim the detection of radio emissions synchronised with the orbit of the planet Proxima b....
user24157
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Can lightning occur in stars like the Sun?
In the Wikipedia article about lightining, the following explanation is given about the electrification process in clouds:
The details of the charging process are still being studied by
scientists, ...
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Do brown dwarfs have stripes?
Brown dwarfs (BD) are often depicted with stripes.
brown dwarf Jupiter
Pictures of BD resemble Jupiter but brown dwarfs ...
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Is there any synthetic spectrum software for neutron star?
Is there any software that can calculate the emergent spectrum of a neutron star photosphere, for Teff is about 1e7K, density is above 1e21-1e22 cm^-3 ? Output line wavelength is about 0-100A is ...
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Why are helium resonance lines called "resonance lines"?
Examples of the use of the term:
Formation of the helium extreme-UV resonance lines
On the Formation of the Resonance Lines of Helium in the Sun (unpaywalled)
Formation of the helium EUV resonance ...
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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 ...
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