Questions tagged [star]
Questions regarding large spheres of plasma undergoing fusion.
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Question about a White Dwarf formula
I have a question regarding the White Dwarf radius formula given on wikipedia, in terms of what units I am supposed to use and what expected values of one variable would be.
https://en.wikipedia.org/...
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How to predict the radius of a Red giant
I am working on a sci-fi that goes over such a large length of time that I will be having stars dying out, and this raises a question that I would need to find an answer to.
How can one predict the ...
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Why do we not call black holes black stars or dark stars?
I've never understood why the term black holes are widely used to describe what is actually a black star or dark star. I mean why name something just because of its extreme space curvature effects? In ...
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Reasonable stellar body stats
I'm working on a video-game (just a hobby) and I'm trying to strike a balance between scientifically accurate enjoyable to explore.
I have here a table of the star types I plan to use. (yes some "...
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Where can I get historical data of tropical longitude of Delta Cancri
I need historical data of tropical longitude of Delta Cancri.
Where can I get it. As of now it is approximately 128 Deg from Vernal Equinox.
Where can I get it's historical data, say from 5000 BC to ...
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What is the distance between Stephenson 2-18 and Earth?
The distance between Earth and Stephenson 2-18 is 19,570 light years (1.15×10¹⁷ miles). The thing that makes this reasonable is because the Earth is in the Milky Way Galaxy and Stephenson 2-18 is in ...
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Could the Methuselah star be evidence that there was a universe before this one?
If the Methuselah star proved to be older than the universe could it be from a previous big bang big crunch cycle in which not everything was crunched? What would be the smallest radius the universe ...
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Latest apoastron of Sirius
The only date that I can find for the latest apoastron of Sirius stars is 2019. Is there a more detailed date with at least the month and/or day. Obviously, it happened in 2019 but can't find any ...
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S0-2 (S2) Diameter/Radius
I'm a student, I am doing an investigation about S0-2. My idea was to take the wavelength that emanates from the star.
When I saw the data from Science magazine I found a problem that was that the ...
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How do the orbits of star systems V871 Centauri (septuple), Gamma Cassiopeiae (octuple), and QZ Carinae (nonuple) work?
Several years ago, I asked the question on here, "How do the orbits of Nu Scorpii and AR Cassiopeiae work?" At the time, these two stellar systems were the most populated (I don't know the ...
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Can a star have one forbidden line or does it have to have many?
My question is: Can a star have one forbidden line, or does it have to have multiple?
Some Examples
I'll be using the O ᴠɪɪ line as an example.
ζ Puppis is a well studied O4Ief star with the O ᴠɪɪ ...
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Is there a easy way to read a star map and discover when and where it was seen and recorded?
I'm making puzzles for a game and found out that you can find out what the night sky would have looked like on any particular date, is there any web site or app that can read a star map and tell ...
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Confusion over habitable zone
I am confused over the habitable zone, as I calculated the expected temperature of Earth (minus greenhouse effects), and it would be -17 C. Which is below the freezing point of water.
I also made a ...
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When did astronomers accept that fixed stars aren't fixed and are at different distances?
Was it when heliocentric model was spreading in the whole world? I saw a model of the solar system that was made in the 18th century where the sun was in the middle and the planets and comets around ...
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Distribution of Galaxy sizes (star count)
First off, I realize how hard this is to even come close to estimating, but I'm trying to get a "general feel" for the distribution of galaxies by star count. I realize everything from rogue ...
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Does most of the Sun's energy and light come from its black-body temperature, due to its massive size alone? Constant crashing of particles?
Stars have to be a certain size to initiate fusion to begin with, correct?
Isn't this why brown dwarfs are considered 'failed stars'?
But wouldn't the Sun (and other stars with sufficient mass, like ...
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On a theoretical young tidally locked planet and its relationship with temperature
I have a question regarding tidally locked planets, regarding the length it takes to reach a certain temperature.
How would one calculate the estimated temperature after a certain amount of time being ...
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Did the Sun's light always peak in the green wavelengths?
So, I know the sun is getting brighter over it's lifespan and I'm wondering how that affects its emission spectrum. The reason I'm asking this is because I find it weird that plants reflect green ...
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Laser pointers spotter
Can I use a laser spotter as a guidance to a star in the sky?
That's if you're by yourself. Here is an example of a spotter on a tripod 10 feet any from my camera!
laser pointer
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What did Galileo believe stars were?
Did he believe stars were attached to the sphere of fixed stars, or did he believe they were suns or did he believe stars weren't attached to anything but just points of light?
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Which static spherically symmetric perfect fluid solutions of Einstein field equations are known to be suitable for stellar models?
Wikipedia's (Static spherically symmetric perfect fluid) short list ends in 2005 and lists only in total 5 such solutions. Does somebody know more?
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Why are WIMP dark matter particles, if Majorana-like, expected to annihilate upon contact? But not neutrinos?
I have heard a lot recently about so-called 'dark stars'; stars that are formed with the help of the gravitational pull of dark matter, or perhaps entirely from self-annihilating Majorana-type dark ...
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Mimimum stellar mass and minimum temperature that triggers hydrogen burning
We can derive the minimum mass of a star in the main sequence using the minimum temperature $T_C$ that triggers hydrogen burning in the core. Then using the stellar structure equations we can derive ...
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Star surface temperature?
I'm already familiar with using the difference in B and V magnitudes to calculate temperature, but Wikipedia (trustworthy source, I know) mentions that U-B, V-R, and R-I are also used depending on ...
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Is Proxima Centauri a Planet?
Proxima Centauri meets all the requirements for Planet status, although it is a star, can an object be a star and a planet at the same time? normally, the answer should be no, but this is the problem ...
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How is parallax really measured?
I understand the basics of how parallax is measured (i.e. two measurements 6 months apart), but I also understand that, in reality, it would have to be more complicated than that, because stellar ...
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Which is brighter, starlight or the CMB?
Which do we receive more energy from, the CMB or starlight? (Not including the sun of course.)
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What do we know about properties of individual stars in the Andromeda Galaxy?
According to the answers to Visible Stars in Andromeda Galaxy, is it possible to distinguish between different stars in Andromeda galaxy. What I am curious about is how much information are we able to ...
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Where to find data about as many stars as possible?
I need computer-readable data about as many stars as possible, with their:
distance to the Earth (or Sun),
their masses,
and if possible:
coordinates,
age,
brightness
distance to the center (...
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Why do white dwarfs cool down so slowly?
I read that when white dwarfs do not proceed with nuclear fusion, the heat radiation from it is solely based on heat it retained in the past
But then, it floats in an almost 0 K empty space. So, why ...
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Is there a way to compare input and output energy of solar fusion to the input and output energy of man made fusion?
The Livermore fusion experiment was said to be 2 megajoules of energy in and 3 megajoules of energy out. However upon closer inspection the facility used 300 megajoules of energy. So man made uses 300 ...
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What would a gas giant, such as Uranus, look like if it were orbiting a sun like star at an Earthlike orbit?
This is a hypothetical. If a gas giant with the approximate mass and density of Uranus existed within the goldilocks range to support life around a star, what would be the conditions on the service. ...
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Why are sometimes the brightest star of a constellation not named alpha?
From the Wikipedia page of Alpha Ursae Majoris:
Alpha Ursae Majoris, Latinised from α Ursae Majoris, formally named Dubhe /ˈdʌbiː/, is, despite being designated "α" (alpha), the second-...
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Negative Rotation Speed (vsini)
I've repeatedly seen the rotation speed of a star given as a negative. Does this mean that the star started spinning in the opposite direction at some point?
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Which star has the highest known metallicity?
Which star has the highest known metallicity?
The highest I know of is Sirius
Which a Metallicity of +0.5, which corresponds to have a Ratio of Fe to H 3 times that of the sun.
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Can a quasi-star develop a stable crust?
Could a quasi-star potentially develop a stable outer layer or crust during its early stage of formation if it were to be bombarded with substantial amounts of matter, coexisting with its core and the ...
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Is WASP-12 a F-type star or a G-type star?
I saw in Wikipedia that WASP-12 is a star with spectral type of G0V while they said its temperature is 6360 K. Does that mean it must be a star with spectral type of F7V or F6V? Its size is not like a ...
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What does G0Vp mean?
I know that "G0V" refers to stars with spectral type G0 but some stars have spectral type G0Vp. What does the extra "p" in there mean?
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What are probabilities of finding a star with the specific stellar type?
I am a programming tutor, and with my student we were writing a program simulating a flight through the cosmos.
I thought that it would be great to make the circles representing stars more realistic. ...
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Calculation of average FWHM by PSF fitting of all the detected stars in the fits image
I need to calculate the FWHM of all the stars detected via the DaoStarFinder package/any other package by performing PSF fitting in Python. Here is the code for my detection.
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How will the expansion of the Sun influence Earth as a celestial body after 5 billion years?
Science news have flooded our news feed again about how our Sun could swallow Earth. This time due to a real documentation of a similar event in an other system.
theguardian
washingtonpost
From what I'...
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What is the correct way to represent the Parallax angle?
I was recently reading about the parallax effect and hence had a doubt about the parallax angle.
A lot of places mention the parallax angle as (θ1 + θ2)/2 while in ...
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Bremsstrahlung's role in the sun
Due to nuclear fusion that produces gamma rays which goes through compton scattering, in the end, on the surface, visible, infrared light ends up as before then, gamma rays lost energy and became x-...
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sun's core - how much x-rays get emitted
We know from the sun, we receive x-rays, gamma-rays but at a very small number of photons.
Question 1: why not much ? is it because most of the x-rays are absorbed in a process of ionization of the ...
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Emitting light from the Sun [closed]
I might be asking too many questions here, but they all seem related to each other and knowing them simultaneously is the only way to understand this subject as I have tried my best googling already.
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do we observe emission spectrum? [duplicate]
When light generated by the fusion in the sun goes through the layers of the sun and finally reaches outer layers and in the end atmosphere of the sun, we know it goes through hydrogen for example. ...
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why couldn't atoms form in the early big bang?
I'm asking about the time when temperature was super high, but at that time we already had proton, neutron, electrons.
It seems they were moving super fast due to temperature being so high.
What I'm ...
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How does carbon end up in the remnants
We know that one way carbon ends up in the interstellar medium which by the way is one or the heavy elements that help form the planet.
But we also know that in the core, carbons fuse with another ...
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How small stars help with planet formation
As I understood, low mass stars in their core go through fusion, but only the fusion of hydrogen happens. When it depletes hydrogen, fusion stops as temperature is still not high enough to support ...
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Finding the uncertainty in period for String-Length Minimization calculation
I wrote a Python script that calculates the period of an unevenly sampled data set using the String-Length Minimization method.
You can read about that method here: A period-finding method for sparse ...
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