Questions tagged [star]
Questions regarding large spheres of plasma undergoing fusion.
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What would happen if a small black hole fell into a star?
Let's say you created a cannon that can shoot small black holes and you shoot it at some star.
Would the star just turn into a black hole silently? Or rather first destabilize and produce a last ...
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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 does lithium fuse at lower temperatures than hydrogen?
This is a basic question, but it's been bugging me. In the Wikipedia article for lithium burning, it states that:
Stars, which by definition must achieve the high temperature (2.5 × 10^6 K) ...
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Can a small black hole orbit a large star?
I recently read about the discovery of a tiny black hole (with only three times the mass of the sun) nicknamed ‘The unicorn’ about 1500 light years from earth. This got me thinking, can this black ...
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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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How do large solar flares compare to flares on other stars?
Solar flares are violent releases of solar magnetic energy. Other stars are also known to have magnetic fields, in some cases much stronger than the Sun. How do the largest stellar flares compare to ...
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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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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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How can 'HD 140283' be older than the universe?
Scientists have known about the star HD 140283, informally nicknamed the Methuselah star, for more than 100 years, since it cruises across the sky at a relatively rapid clip. The star moves at about ...
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What is it like to see a brown dwarf turn into a star?
Brown dwarfs/failed stars can actually become stars, if they exceed a mass limit of about 80 Jupiter masses. This is when the internal pressure and temperature at the core become high enough to ...
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Modeling binary star using MESA
I'm trying to model a binary star using the MESA (Modules for Experiments in Stellar Astrophysics docs) code with an orbital period of 10 days with the scenario where mass transfers starts after the ...
CommunityBot
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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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Which star system has the highest multiplicity (# of stars), whose orbits are known for all stars?
I posed a question on here a couple months or so ago about the orbital patterns of each of the seven stars in the two septuple star systems Nu Scorpii and AR Cassiopeiae. It went unanswered for more ...
CommunityBot
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Can you see the stars when it is trickling?
I am writing a book with the following scene in one chapter: It is trickling and my protagonists are outside looking into the night sky, looking to the stars. Reviewing the scene I am wondering: Is ...
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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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When did astronomy first discover that the stars are bigger than the moon?
We take it for granted these days that the stars are bigger than the planets and the moons. But when you look at the sky, it does not appear this way.
The Moon looks bigger and brighter than the stars....
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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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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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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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Is the Sun really burning and getting smaller?
Is the Sun really burning and getting smaller? If so, because there is no air in space, what can be keeping it burning and what materials get burnt? If no air is required, what can speed up or can ...
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Is there any planet bigger than a star?
Or a star smaller than a planet?
Which star and planet would be an example of this?
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Does any iron fuse in stars before they go supernova?
I understand that iron and all heavier elements consume more energy to produce than they make, and that is what eventually leads to a supernova. I also understand that a lot of the heavier elements ...
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If an orbit is shifting due to orbital precession, is it still a Keplerian orbit?
I was thinking about orbits a few days ago, and realized that orbits shift/precess naturally. Given that a two-body problem with a star and a planet, if the planet has an eccentric orbit that ...
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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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Why do some stars twinkle more than others?
This is a child's question I failed to answer. When observing some stars with naked eye, some stars (e.g. Regulus) appeared to blink significantly more than others, but I did not have the patience to ...
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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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When exactly does Sirius shine into the queen's chamber of the Great Pyramid?
I read that Great Pyramid was built to resonate with Sirius by aligning an airshaft that connected to queen's chamber. That is, the light of Sirius going through the shaft would be able to shine into ...
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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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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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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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Which star has the lowest absolute magnitude?
I have seen many lists of stars with the most luminosity, mass, and temperature, but I have never seen one that is about absolute magnitude. So I'm wondering, which star has the lowest absolute ...
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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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