Questions tagged [star]
Questions regarding large spheres of plasma undergoing fusion.
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Star like light moving in the sky, what could it be? [closed]
I was camping this weekend away from the city, so my friends and I decided to spend one of the nights watching the sky, since it's impossible to see anything around where we live. After a little while,...
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What exactly is the "paradox" in Olber's Paradox?
To the extent of my understanding, Olber’s paradox states that if the universe was static and homogeneous, we should see a star at every point in the night sky and therefore the night sky should be ...
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Is the light we see from stars extremely old?
Our nearest star Proxima Centauri is 4.243 light years away from Earth.
Does that mean we are seeing light that is 4.243 years old everyday?
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Is there enough hydrogen left after a star dies so another star will have enough to light up?
A star consumes quite a lot of hydrogen in its life, and is pretty much "vacuuming" everything in its vicinity. After it dies (eventually by supernova which will spread all its composition over light ...
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How often do stars pass within 1 light year of the Sun?
Interstellar exchange of massive objects is difficult across several light years. But as the stars orbit the galaxy the distances between them change. I don't find data for neighbor star distances ...
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What are the odds that the Sun hits another star?
The Sun moves around the Milky Way disk in the same direction as most of the other stars in our galaxy (prograde). But there are a number of older stars in the galactic halo that move in retrograde ...
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Is there a theoretical maximum size limit for a star?
Some stars are simply huge. Eventually, though, wouldn't there be simply too much pressure or mass for the star to sustain itself? Wouldn't it eventually collapse into a black hole?
Is there a ...
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Statistically, what would the average distance of the closest black hole be?
The closest confirmed black hole is several thousand light years away from earth. Our galaxy has about 100 billion stars. I didn't find any reliable information on the black hole count of ratio versus ...
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Where can I find a catalog of all stars in the Milky Way?
Is there a catalog of all known stars or brightest stars in our galaxy? Preferably with some sort of galactic coordinates instead of just night sky coordinates (right ascension, etc.) I'm trying to ...
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Does the Sun turn around a big star?
The Moon orbits the Earth.
The Earth orbits the Sun.
Does the Sun orbit another bigger star?
If so, does this star orbit, in turn, a very big star?
... etc ...
What are all the intermediate ...
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Why does iron consume more energy in the fusion process than it produces?
I understand that once a star starts fusing iron, it's doomed to collapse because iron fusion requires more energy than it releases in the process, allowing the opposing gravity of the star to cause ...
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What equipment and techniques were used to study Betelgeuse's diameter in 1920?
Comments below What is the maximum distance measurable with parallax? discuss challenges associated with parallax measurements of Betelgeuse and link to Wikipedia’s Betelgeuse; Distance measurements ...
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Will new stars stop forming at some point of time?
New stars keep forming in the universe thanks to all the nebulae. Now, we need Hydrogen to form stars and there would a time when all the hydrogen will get exhausted, and no more star formation will ...
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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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What are the chances of a star colliding with another during a galactic collision?
My specific example for the question is the future collision of the galaxies Milky Way (our own galaxy) and Andromeda in a couple billion years. The star in question is obviously the sun in this case. ...
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Requesting book references for a non-expert person with math background or just a non-expert person
I've just finished my masters degree (to be exact previous week ^_^). And I'm completing my collection of applications of my studies. During previous year I started reading about Robotics and Coding ...
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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 this web on the surface of the Sun?
I was going through my Social Media Feed and found the attached post too frequent. The caption reads this is the best image of our Sun. Just as an example, the Universe Today's This is the Highest ...
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Why are there no green stars?
There are red stars, and orange stars, and yellow stars, and blue stars, and they are all understandable save the fact that there is a 'gap': There are no green stars.
Is this because of hydrogen's ...
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Are we made of the stuff of one star or more stars?
[T]his coincidence enabled stars in the late stages of their lives to turn helium into carbon, oxygen and most of the other atoms that you and I are made of. [...] [W]e're made of star stuff.
Max ...
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Why are orbits elliptical instead of circular?
Why do planets rotate around a star in a specific elliptical orbit with the star at one of it's foci? Why isn't the orbit a circle?
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What is that donut-shaped object I see in my telescope? [duplicate]
I was looking through my telescope for the first time and came across this weird star. I think its a celestial donut but im not sure.
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Is it possible to determine an observer's position on Earth from a photo of the night sky and the time of the shot?
To my knowledge, this question can be related to celestial navigation on one hand and to attitude (or orientation) determination from stars direction on the other hand. However the combination of this ...
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What is this rapidly twinkling red, blue, and white star I saw?
Last night, I was on my balcony at 1AM (PST) and I looked up and saw two stars near the horizon (I'd guess ~30 degrees above the horizon), and they were "twinkling" about twice as fast as other stars ...
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What is the spectral reflectance of starlight in a close binary?
Ignore the Blender Monkey! (from here)
In a close-orbiting binary pair, a small but significant fraction of the light from each star falls upon the other, and the result has to be carefully modeled ...
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What causes horizontal and vertical lines coming out of pictures of stars?
What causes the horizontal and vertical lines coming out of pictures of stars, instead of them simply appearing as circles? For example, this picture from Wikipedia: .
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How long does it take a star to transition from main sequence to red giant?
I have read that it takes billions of years for stars of approximately the size of the Sun to get through the main sequence, after which it will enter the red giant phase. When that happens, how long ...
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Is it possible for a star to orbit a planet?
Is it possible for a red dwarf to orbit a gas giant?
OR
Has this happened and it is just assumed that the gas giant is orbiting the star?
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Is there a better explanation of this picture showing the very distant star "Earendel"?
"Close-up of the tiny region where Earendel happened to fall right on top of the narrow line where the magnification increases by (tens of) thousands of times. A cluster of many stars is seen ...
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Metallicity of Celestial Objects: Why "Metal = Non-metal"?
Metallicity of objects refers to the amount of chemical elements present in it other than Hydrogen and Helium.
Note: The other elements may or may not be actual ...
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Why do stars appear to twinkle?
Sometimes at night you will look up to the stars and they will appear to twinkle, getting brighter and darker in bursts.
Why does this happen? Is this because of our atmosphere? Would they twinkle ...
user96
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Hydrogen burning vs Hydrogen fusing
Does the term "Hydrogen burning" mean the same as "Hydrogen fusing" in astronomy? If not, then what is the product of "Hydrogen burning"? Assume the product of "...
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Calculate Distance To Stars
I was just watching a lecture from Carl Sagan. He talked about figuring out the distance to the stars; it got me interested in learning more about the subject.
As far as I know, the Inverse square ...
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What was the absolute limit to the possible sizes of the first stars formed from "primordial material with no metals"?
This answer to Why don't or (can't) stars be more than 325 or so times the mass of the sun? What limits their size? includes the following:
...The upper limit you refer to is for compositions similar ...
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Mass of black holes compared to parent star
What is the range of percentage mass of parent star left in a stellar black hole directly after its formation?
What factors determine this number for a specific case?
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Without using absolute magnitudes or isochrones, how might we tell a star's age and evolutionary status?
Usual methods of estimating stellar ages involve isochrone approximations. It can also help to estimate a star's radius by correlating its absolute magnitude with effective temperature and apparent ...
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Where do the heavier elements come from?
Partly inspired by this question, the end result of stellar fusion is Iron-56 (eventually, after some decay). Then it explodes. How/where then to the heavier elements come from. The answer here ...
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Why are there no stars on New Horizons images of Pluto
I followed the New Horizons Mission a little, and saw among others this image of Pluto:
I wonder, why you can't see any stars on it. As far as my very basic knowledge in astronomy goes, I think you ...
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Is there a retrograde star that passes closer to the galactic center than our Sun?
Our Sun is moving in a prograde orbit around the galactic center with a distance of about 8 kpc. This paper says there are many retrograde stars in the galactic halo 10-20 kpc from the galactic ...
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Why do stars twinkle but planets don't [duplicate]
Many people say that stars twinkle because of Earth's atmosphere. However, the atmosphere is still there when we look at planets and don't see they twinkling.
Is there a clear scientific consensual ...
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If two stars collide, what is the probability that they merge to form a single star?
After looking at What are the odds that the Sun hits another star? and answering it (crudely), now I'd like to ask the following:
What is the probability that if two stars collide, their cores merge ...
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What is the distance from Alpha Centauri to Barnard's Star?
Alpha Centauri AB is the closest star system to Earth (4.366 ly), followed closely by Barnard's star (5.988 ly). The closest star system to Alpha Centauri is Luhman 16 (3.8 ly from α Cen). So I am ...
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What would happen if a Sun-like star were to consume a Jupiter-like planet?
A substantial number of discovered exoplanet systems are likely contain more than one gas giant with distances far closer to the star than in our solar system.
It is known that in solar system ...
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Why don't we see purple stars
I know that we don't see green stars because in blackbody radiation star doesn't produce one spectrum.
The stars that have peaks in the green spectrum produce other spectrum in nearly same amout. ...
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Why don't we detect planets around OB stars and no terrestrial planets around A or early F stars?
Looking at an exoplanet database, I noticed that there are very few planets detected around main-sequence OBA stars, and most of them are gas giants/brown dwarfs. Why can't we detect low-mass planets ...
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Stars in constellation patterns by catalogue number?
I need a resource that can tell me the stars that make up a constellation (pattern), preferably by Henry Draper or some catalogue number? All i can find is lists of every star in a constellation (area)...
user16454
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Best way to simulate star sizes to scale in celestial sphere
Using the Hipparcos catalogue, I am trying to create a celestial sphere. As all the stars are a fixed distance from the centre of this sphere, the only way to differentiate the distances and magnitude ...
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What if hypothetically Ton 618 could have been a star
Assuming Ton 618, the largest ultra massive black hole wasn’t the result of feasting on near by matter but was hypothetically once a single star body. How large in terms of size would TON 618 have ...
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Why does gas form a star instead of a black hole?
When a space gas gets pulled together a star is formed. On the other hand, when a massive star dies, it collapses to a black hole.
You would think that the initial mass of the gas would be bigger ...
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How many stars and galaxies can be seen by the naked eye?
How many of the luminous dots that we see naked are galaxies and not stars from our galaxy?
I imagine that the majority of the luminous points that we see naked eye during the night, are actually ...
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