Questions tagged [star]
Questions regarding large spheres of plasma undergoing fusion.
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How to find the luminosity of stars from the Gaia DR3 archive?
My main objective is to find the radius(or relative size) of the stars from the Gaia DR3 archive. However as I was unable to query the radius directly I am looking into the Stefan-Bolzmann Law which ...
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Red light that moves back and forth and then moves upwards [closed]
I saw ared light flashing in the sky that moved about a distance in a straight line and then returned to the original place and moved upwards. I have been seeing this about a year from now. And it ...
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Skewing of data regarding velocities of stars
For a school project I am currently determining the location of sagittarius A* (the supermassive black hole at the center of the milky way). I have analyzed about 1 million stars and their velocities. ...
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Estimate the core pressure of a star
Consider a small column at a distance $r$ from the center of a star with a height of $\Delta r$ and a base area of $\Delta S$, a density within the column approximated to be uniform for a value $\rho(...
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Can a relatively small addition of matter to a small volume of a star turn it into a supernova?
Can a relatively small addition of matter to a small volume of a star turn it into a supernova?
The rate of fusion in the CNO cycle increases very rapidly with increasing temperature, as shown in the ...
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Why is Epsilon Indi Ab 2° Celsius?
I was reading the Wikipedia page for the exoplanet Epsilon Indi Ab.
It orbits around its parent star every 173.6 years in a distance of 28.4 AU as provided in the first infobox of the article.
The ...
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What would sunsets look like around different star types?
I have always wondered what a sunset would look like around different types of stars. I have tried to do some research into the types of light refraction, but I cannot find any answers anywhere, and ...
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Required temperature for a nova
On the wikipedia page of the nova is said that the CNO cyle, which converts hydrogen into helium, starts on the surface of the white dwarf when the temperature reaches about 20 million K.
My question ...
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In the onion-like elemental layers of a large mature star the neon is closer to the surface than oxygen, even though it is more massive... Why?
On both Wikipedia (Stellar evolution) and Lumen Learning (The Evolution of more Massive Stars) the Neon layer is depicted as being external to the Oxygen layer despite the fact that neon is heavier ...
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Star forming regions
Some star forming regions, like Bok globules (which contain stars that still haven't dispersed their molecular hydrogen and cosmic dust shell) appear dark compared to the rest of the H II in which ...
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Can a star be made of sun spots?
Can there be a star that is made of the same matter of our sun spots? What would the illumination be like?
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What's the density of Proxima Centauri's photosphere?
Proxima Centauri is a red dwarf much denser (33X on average) than the sun. Yet I'm not finding anything about Proxima Centauri's photosphere. The Sun's photosphere is only 0.2 g/m3 (1/10,000th of sea ...
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Is it theoretically possible for the Sun to go dark?
If photons potentially take millions/billions of years to find their way to the surface of the Sun from the core, bouncing off billions of other atoms on their way. Is it theoretically possible to ...
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Are spectral subtypes a logarithmic scale, or a linear one?
Are spectral subclasses logarithmic? I can't seem to find any source on whether they're linear or logarithmic. For reference, by spectral subtypes I mean, for example, G2 vs G3 stars.
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python question-discrepancy between number of stars found
Ok, I get that this is a long question but it's ok if you don't know just thought I'd give this a try anyway. I get that it's a long shot. Basically I'm trying to replicate a methodology used in the ...
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When a star enters a red giant phase, does the pressure in its core increase or decrease?
When a star becomes a red giant, does the pressure in its core increase or decrease?
From one side, the only source of pressure in a star is gravity. A red giant is much larger than an ordinary star, ...
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What was the first nebulae of the first class?
On Wikipedia, it describes the Tarantula nebula as
the second of the "Nebulae of the First Class",
Wikipedia says that a Nebulae of the First Class is a Nebula with no other stars visible ...
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Why do larger mass stars form quicker?
I understand that larger mass stars form faster than lower mass stars. After doing research, I found it was because they got heated faster. But wouldn't this slow down the process as the higher ...
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Is it possible that some "stars" or "black holes" have "wormholes" in their center? [closed]
Seems like if the mass of a "star" or "black hole" changed without absorbing or expelling anything, then that would be an indicator that there is a "wormhole" inside.
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Why does Helix Nebula look like an eye?
The infrared lights, the material clumps that radiate and the whole view resembling a celestial firework or giant eye
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Comprehensive Stellar Evolution Article
Is there an article that comprehensively covers stellar evolution, from start to finish. I've found articles on this, one in an introduction to a stellar evolution model, and I am searching for more. ...
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Single, binary, triple, .. fraction of star systems in our galaxy by mass
What is the fraction of single, binary, triple and so on systems as a function of one of the stars masses (or their sum)?
This can be either derived from simulation or measurement.
I feel like I have ...
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What direction do Herbig Haro outflows go from?
After doing some research about Herbig Haro objects, I found that the outflows are formed perpendicular to the circumstellar disk. Is that the same direction as the star's rotation, or is it the ...
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What element drives pulsations in T Tauri Stars?
What element drives pulsations on T Tauri stars? I understand that T Tauri stars are variable and pulsate, and I also know that other stars pulsate as well. My thinking is that a T Tauri star would ...
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Tracking variable stars?
Is there a website or application I can use do track the brightness of variable stars and notify of any unusual or particularly spectacular changes.
I am particularly interested in tracking the blaze ...
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Why does nuclear fusion generate heat?
I understand that nuclear fusion generates energy in the form of gamma-rays (as in the pp chain), but how does that translate into heat in the star's core? Or is the heat just generated by ...
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What do you call a protostar with more than 10 solar masses?
PMS Stars with less than 3 solar masses are T Tauri stars, and PMS stars between 3 and 10 solar masses are herbig ae/be stars, so what do you call a star with more than 10 solar masses? Is there ...
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Hayashi Track vs Red Giant branch
Are the red Giant branch and the Hayashi track the same thing? After doing some research, I found some similarities between the two, such as both aree fully convective. However, the T Tauri phase does ...
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Where in a star are the spectral absorption lines formed?
This question was inspired by a recent Cool Worlds video "The Star That Shouldn't Exist", in which one of the speculative solutions to Przybylski’s Star's strange spectrum is aliens "...
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Why do red dwarf (M-type) stars give off such violent flares and CMEs, out of proportion to their size and temperature?
Dr. Becky (Smethurst) just posted a new YouTube video mentioning, as I have heard many times, that it might not be possible for life to form on planets around Red Dwarf (M) stars because they would ...
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How far away are the two components of the Rigel system?
How far away is Rigel A and B and what is the angular diameter of Rigel B from A?
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Pure Lithium Star
Suppose by some miracle a large molecular cloud of pure lithium assembled itself in space, then gravitationally collapsed.
What would the result look like? Would it be a star of some sort (fusing the ...
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'Star' appeared dimmer and dimmer over multiple days before disappearing. What could this have been?
This happened a little while ago but I've just been thinking about it!
I was in Wales for a holiday, and over the period of 7 days, a particularly bright 'star'(or at least a bright dot that looked ...
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What were the specifics of the photos taken by Sir Arthur Eddington during the Eddington expedition that supported Einstein's Theory
I know that Sir Arthur Eddington went to South American to photograph stars around an eclipse to see if they seemed to change position when the light past by the Sun relative to when the light didn't ...
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What are the most up to date, accepted, evolution stages of big stars that end in compact objects or a planetary nebula?
There are numerous charts and diagrams showing the stages of stellar evolution, as:
or
among many more (you can find several after googling a little), for example.
When I studied my B.Sc. on Physics,...
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Lifespan of neutron stars and black dwarfs in terms of mass in years
Stars have a lifespan scaling as $1/M^{2.5}_\star$ for sunlike stars or more generally $t\sim 1/M^3$ for general stars (more or less), black holes have a lifespan (according to simple Hawking ...
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I saw a strange cluster of stars, help! [duplicate]
On January 1, 2024 in the sky above Almaty region, at about 19:05-19:10, I saw a line of stars that flew in one even line that disappeared in the distance, the stars were not very bright, but they ...
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Neutral vs ionized mean molecular weights
I am confused about the calculation of mean molecular weights, especially for ionized particles. From my understanding, the mean molecular weight $\mu$ is the average mass per the number of particles:
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Are there stars that orbit other stars, such that the barycenter is inside one of them?
I know binary stars exist but I mean a star which orbits with a barycenter that is inside another star, much like a moon. Why is such a system so rare?
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Are there any bright *main-sequence* K-type stars in the night sky? Or are all of them giants?
It's well known that stars of a higher (i.e. hotter) spectral class have higher luminosities, due to their larger radii and hotter temperatures. Stars of spectral types O through G have no problem ...
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What star is this?
From this image, can you help me identify the star circled in yellow? This picture was taken mostly above my head, but facing slightly southeast, from the southwestern corner of Virginia.
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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 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 does metallicity change the mass-radius and mass-luminosity relations in main-sequence stars?
I'm building a star cluster for my space opera setting and I'd like to include some highly-metallic stars as anomalies and resources.
Wikipedia defines stellar metallicity as the fraction of a star's ...
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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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