Questions tagged [sun]
The Sun is an almost perfectly symmetric yellow dwarf star [spectral class G2V] which is at the center of our Solar System.
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How to identify the composition of sun if it is treated like a blackbody? [duplicate]
The sun is usually assumed to be approximately very close to a blackbody, but using spectroscopy it is concluded that the sun is made up of Hydrogen and Helium because the lines corresponding to those ...
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Why do we not see Sun red in daytime? [duplicate]
I have had this question strike to me as when thinking about the reddish colour of sun during sunsets which is happening through rayleigh scattering , the highly energetic wavelength of colours are ...
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How does Viscosity of the Sun varies as we go from core to the convective zone?
How does Viscosity of the Sun varies with its radius?
For. eg, Here is the graph of the Density of the sun v/s radius. I am looking for the Viscosity v/s radius plot.
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Is sun orbiting the center of the Milky Way? [closed]
Are all the celestial bodies in our galaxy (along with the Sun) orbiting the center of the Milky Way Galaxy?
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Why is mercury the closest planet to the Sun? [closed]
I just want a solid reasoning that why Mercury is the first planet away from the Sun, then Venus, then Earth, then Mars and so on.
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How do you calculate light attenuation by wavelength at a given air mass coefficient?
I am trying to get a good view of light wavelength distribution as a function of viewing angle, with a specific interest as $z \approx 90^\circ$ near the horizon (sunrise/sunset). Air mass ...
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How do the atoms and electrons move around space when the solar core presses them into a dense plasma? [closed]
It takes a lot of intelligence to compute the center of the sun. As far as I imagine, it's compressed by the hand of gravity and high energy fusion radiation wants to escape one way or the other. ...
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Is the Sun considered to be a black body as a whole or it is only the photosphere which is a black body?
I am having some difficulties understating how fusion inside the Sun is connected to the Sun being a blackbody. How do the photons transfer to the photosphere? Is the amount of transferred energy less ...
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Why doesn't a black body absorb its own radiation?
If black bodies absorb all the radiation and emit radiation by themselves, why don't they absorb their own emitted radiation? We shouldn't see the sun for example, since it's a black body.
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What nuclear fusion reactions occur to form lithium in the sun?
Hydrogen nuclei (deuterium) fuse together to form a He-4 nucleus.
I looked up about how lithium exists in the sun and all of the results on Google I looked through kind of dodge the question and ...
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How big can solar flares get and could they boil away Earth's atmosphere?
Is there a known theoretical maximum size for a solar flare and would it mean curtains for life on Earth?
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If there is no oxygen in space what does the sunshine burn for fuel? [duplicate]
Since there is no oxygen in space how does the sun burn fuel?
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Why are planetary orbits stable given accumulation of forces due to solar wind?
The solar system is more than 4 billion years old. Ever present solar winds which emanates from the sun consists of photons, hydrogen and helium. The momentum transfer from photons upon contact with ...
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Calculate the solar central density using an equations of stellar structure
How can I calculate the solar central density $\rho_C = 150 \textrm{g cm}^{-3}$ using one of the equations of stellar structure like the the mass distribution equation $\frac{dM(r)}{dr}=4 \pi r^2 \rho(...
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Sun light takes 1,000/30,000/100,000/170,000/1,000,000 years bouncing around inside to then reach the Earth
When light (photon particle) is generated inside the Sun, it takes a long time to bounce around inside to later escape and travel outwards.
Neutrinos escape immediately.
The numbers for the years ...
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Intensive reflection of sunlight at sunrise/sunset
I would like to ask about the phenomenon, which always occurs near sunrise/sunset.
If I could be more precise. When Sun goes down its strong reflection is to be spotted usually at trees, but also ...
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Solar neutrino spectrum: why are there two lines for beryllium?
I have a follow-up question to this one:
Solar neutrino Spectrum - Why are there discrete energies for Be and pep?
I understand why the lines for $^{7}\text{Be}$ and $pep$ are discrete, but why do we ...
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Do solar panels act as an electrical load on the sun?
We know that the sun uses nuclear fusion to generate sunlight and heat energy. If we are using solar panels to harvest solar energy, aren't we putting some electrical load(resistance) on the sun? If ...
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What is rate of emission of heat from a body in space?
I want to know the answer to the question in the title, I want to see how much heat energy
can a body emit during present in lonely space without any contact of other body.
By knowing this I can ...
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Why Do Polarizers Make The Sky Bluer and The Trees Greener?
I've been reading a lot about polarization and I have pretty much understood the physics behind the phenomenon. However, until now I couldn't find a scientific reference that explains clearly why the ...
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Magnetic explosions on Sun
They say (in popular videos and articles) that tangled magnetic fields on Sun explode. But i don't understand why and how magnetic fields, tangled or not, explode. Could anyone explain?
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What's the lifespan of Deuterium and Helium-3 in the Sun?
What's the lifespan of Deuterium and Helium-3 in the sun?
How long on average, the Deuterium and Helium-3 atoms last in the Sun's core?
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How much energy holds the full visible light spectrum? Same to heat absorbed by back color?
I would love to know how much energy a black body absorbs from the visible light.
In the following site we can calculate the eV of a given wavelength, but if I'd like to know the sum of eV for the ...
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How much energy from gravitatational waves does the sun absorb?
I was wondering how much energy from gravitational waves the sun could absorb since it is so big and also has a massive gravitational pull. Is it possible for the sun to trap gravitational waves ...
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How does the DKIST filter out photosphere light?
How does DKIST filter out light from the sun's photosphere while capturing light from the chromosphere? I'd like to know the physical or mathematical mechanics that accomplish this.
If the naive ...
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How long before the Sun has given off enough energy=mass for a one meter thick Dyson Sphere at earths orbit?
Just for fun: As energy can be converted into mass - what if we had some kind of magic technology which can convert photons into carbon atoms with 100% efficiency. I realize its not as easy as just ...
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Why are sunspots cooler than the other regions?
The Sunspots appear darker than the other regions because they are cooler; and I know that according the Babcock model, the Sunspots are places where the tangled magnetic fields burst out through the ...
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How much energy from neutrinos does a Helium flash create?
How much energy from neutrinos is given of by a solar mass star when it undergoes a Helium flash?
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What percentage of sunlight isn't scattered by the atmosphere?
What percentage of sunlight isn't scattered by the atmosphere and instead will arrive at your eyes directly from the sun.
It's been aksed here before but a proper answer hasn't been given.
I was ...
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What exactly is the "Yield Function" of a neutron monitor?
I have been reading papers related to the theoretical computation of a neutron monitor count rate, which is defined as the integral of the "yield function" of the specific neutron monitor ...
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Does the RA and DEC of the sun change with time?
I'm almost certainly misreading this, but it's said that "one of the great advantages of the equatorial system is that the RA and Dec of a star do not change with time, at least over short ...
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What effects would a substance as hot as the sun have on its surroundings on Earth? [closed]
If you had an object, about the size of an adult human, that was as hot as the surface of the sun that somehow doesn't cool down, what effect would it have on its surroundings? Would it just vapourise ...
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On average, how often does any given hydrogen nucleus run into another hydrogen nucleus in the Sun?
I think there is a misprint in an article. I will include the link if you don't mind and cut paste the sentence that I think is a misprint. Here is the link
https://www.abc.net.au/science/articles/...
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How much is the UV index reduced when under the shade approximately?
Assuming simple conditions e.g. sunny, bright day (no clouds), sun is directly overhead, what becomes the effective UV index for someone who is outdoors under solid shade (e.g. sitting under a ...
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Is the total gravitational energy in the sun greater than the energy that is produced by the sum total of the nuclear fusion contained therein?
I think this is off topic, maybe an astronomy question. Unlike a chemical chain reaction or a fission chain reaction I believe fusion cannot sustain inself. Is more energy going out than is going in ...
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Does dusk really remain for a shorter period of time at the equator?
It is said that the dusk remains for shorter time at equator than the poles. Because, the equator rotates faster than poles. But it is also true that time is the same in every latitude, and if it's ...
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Absorption spectrum of white light of the Sun
When some photons in the white light from the sun are absorbed, this means some wavelengths will be missing, so how does that light still appear 'white', although some of its constituents are missing?
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How exactly does one reaction of nuclear fussion exactly produce EMR of different types? [closed]
Electromagnetic radiation from sun is more likely produced by the nuclear fusion, and at a go radiation is released but how is it possible for different types of radiation to be produced such as, ...
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How to calculate amount of energy an area receives from sunlight?
I recently read this article, but is quite unclear on how it got those equations and used them to find the amount of energy (J) an area receives from sunlight over a period of time (s). Does anyone ...
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Do solar flares move the dust on the surface of the Moon?
The TV show For All Mankind has a reputation for scientific accuracy, so I think it's fair game to ask if it lives up to this reputation.
In this video clip, we see the dust on the surface of the Moon ...
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What is the minimum size of an object to cast a shadow on the entire Earth?
When I fly up(don't ask me how), I see how my Sun's shadow on Earth is getting bigger but dimmer as the Sun's light is reflected from other objects.
As I flew higher and higher in the direction of the ...
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Does the index of refraction of the sun's corona and solar wind contribute to the bending of light
It's not hard to imagine that the sun's corona and surrounding solar winds have an optical density that can affect the index of refraction near the surface of the sun and bend light in these regions. ...
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Is there any clear and concrete proof that says the Earth is rotating and orbiting? [duplicate]
As the title states, I am wondering if there exists a clear and concrete proof that proves that the earth is revolving around the sun on an orbit, and proves that the sun is not revolving around the ...
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Earth is spiraling away from Sun at rate of 1.5cm per year due to mass loss of Sun? How it was calculated? [closed]
My physics teacher asked if we could calculate the rate at which Earth moves away from the Sun due to the mass loss of the Sun. It's very sensible for me to understand that Earth is spiraling away ...
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How is the solar magnetic field produced?
I have been trying to understand the magnetic field creation mechanism. I know that its origin is not perfectly understood, but what is currently believed (as I know) is that the magnetic fields ...
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Temperature and latitude
Currently I read this excerpt on a school power point that stated the following:
" The sun is closer to the equator than the poles.
Therefore the sun’s rays have less distance to travel to the ...
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Have solar wind particles escaped the Sun's gravity or will they eventually return back?
I've read that solar wind consists of hydrogen atoms that are, near the Earth, travelling at about 450 km/s. This is only 3/4 of the Sun's escape velocity, but then the Earth is also 150 million km ...
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Black body side of the Moon
A few closely related questions regrading the Moon thermodynamics:
The Moon is clearly not a black body, as it reflects a great deal of radiation incident on it. Still, it does absorb some radiation ...
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Does pressure increasing or decreasing due to temperature have an impact on the Sun Core's "Thermostat"?
Firstly, thank you for reading this post.
I have a question regarding how the Sun regulates its nuclear fusion rate in its core. This is commonly known as the Sun's thermostat. This is a homework ...
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Colours of the sky if sun was blue?
What would be the colours of the sky at different points of the day if the sun was a blue star? This is assuming that our earth is at a similar distance away from the surface of the blue sun as it is ...
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