Questions tagged [star-systems]
Questions regarding two or more stars gravitationally bound to each other
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When calculating the mass of stars, is it considered that additional mass could be added because of pair-production?
I would like to know that, since stars emit a lot of photons where some of them could be producing electrons-positrons pairs, if its mass affects the calculations, and if because of this is different ...
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What does a + (plus) mean in stellar classification?
I've noticed some stellar classifications might look like this:
A0IV+G: (HD 70003)
F3IV+F0IV (HD 82434)
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how much time do Alpha Centauri A and B have?
According to Wikipedia:
Alpha Centauri A: $M=1.100 M_\odot$ and $L = 1.519 L_\odot$
Alpha Centauri B: $M=0.907M_\odot$ and $L=0.5002L_\odot$
They are 5-6 billion years old (you can assume they are 5.5 ...
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Binary Star System
If our Sun was a part of a Binary Star System, would it be too hot to live on Earth ? With two Suns, would we get double the heat from them ,than from our Sun alone ?
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Nomenclature of Interstellar Objects and Stars
I posted this question on the space exploration SE but people recommended that it would be more on-topic here. Could someone please help by giving some definite laws of nomenclature for celestial ...
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Virial ratio behaviour
I think I didn't understand something about virial theorem for an $N$-body system, for instance the behaviour of virial ratio $T/\Omega$, with $T$ kinetic energy and $\Omega$ gravitational potential ...
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What is the upper bound of number of stable interacting stars in a star system?
I remember very well reading in an article that it's impossible to have a stable star system of 4 or more stars. The article justified its claim discussing about the complexity such systems would have ...
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Does a star's rotation always match a planet's orbit?
For a planet orbiting a star, is it ever possible for a star to be rotating in the opposite way on it's own axis compared to the planet that is orbiting the star?
Or do gravitational forces mean the ...
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Eta Cassiopeiae star type; G0V? F9V? Both?
For a story I am looking into the star system of Eta Cassiopeiae, which is a binary with a main sequence star called Achird (very similar to the sun) and a K7V star.
The issue I am running into is the ...
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Fate of lone spiral galaxies?
I know Hubble's galaxy classification scheme and the bifurcation from elliptical galaxies into two types of spiral ones. I am also aware of different theories on how spiral galaxies form e.g. through ...
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What are hot and cold stellar systems?
My idea of the matter is: hot stellar systems are which form of objects which have a velocity standard deviation comparable to their mean velocity. Is this correct? If it is, is there a $\frac{\...
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Celestron Nexstar 102GT
Good day folks.
My Grandson would like to start using this Telescope Celestron Nexstar GT102, has been in the basement for years, and unfortunately, we appear to have misplaced the eyepieces.
Just ...
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Is it possible to have a trinary star system with a planet that orbits their barycenter?
I am trying to model a 3-star system with a planet. The three stars have the same mass. I have gotten the stars (Yellow, Pink, Blue) into a stable orbit. However, I am wondering if a "free-...
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Why are stars still distant from one another? [duplicate]
Why are stars so far from each other? Shouldn't gravity pull them closer over time? And if the effects of gravity are negligible is there an explanation why stars have to be so distant from one ...
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Fractional contribution of secondary star
What do we mean by "the luminosity fraction" and "the fractional contribution of the secondary star" of binary stars? can anyone suggest any method to calculate them theoretically?...
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Why is detecting brown dwarfs difficult?
Why is detecting brown dwarf stars tedious and not always successful? They emit light in the infrared region, and given that we're surrounded by state-of-the-art technology in space today, why haven't ...
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Closest star system to Alpha Centauri?
The closest star system to our Solar System is Alpha Centauri.
But is our Solar System the closest star system to Alpha Centuari?
If not, which star system is?
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How many stars are there max and average per galaxy?
What is the range of the number of stars possible in a galaxy? What is the rough average?
Googling leads to vague answers, things like "billions upon billions". But what is a more pinpointed set of ...
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PHOEBE 2.2 Documentation, components and semi-major axis definitions
I'm looking at PHOEBE 2.2 Documentation, specifically at a tutorial about constraints
What are Constraints?
Constraints live in their own context of the Bundle, and many are created by default - ...
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How Does Earth Move In Relation To The Stars
In my simulation, I have stars scattered around Earth, all stars are the same distance from the center of the Earth and positioned based on their right ascension and declination like so:
I am ...
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Can mean motion resonances make orbits more unstable rather than more stable?
This paper on closely packed orbit simulation seems to suggest that having the planets in first and second order resonances decreases the time till orbits cross each other. I'd got the impression that ...
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About more than 15 stars moving in straight line through the sky [duplicate]
I had seen more than 15 stars are moved in a straight line through the sky just like a train. And the distance between each star was not same, some of them were near and some of them were far. The ...
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Derivation of a formula for the mass of a tidal bulge and tidal torque
I've been looking into the tidal mechanism for a binary star system and seem to have hit a brick wall. In the literature (see below), little explanation is given to justify the equations (9.60), (9.61)...
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Maxwell stress contribution to $\nabla \cdot \mathbf{P}$ in the Navier-Stokes equation for fluid in stars
I was reading through the following extract outlining how the Maxwell stress contributes to the $\nabla \cdot \mathbf{P}$ term of the Navier-Stokes equation for fluids in a star. Here $\mathbf{P}$ is ...
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Why are there no stars visible in cislunar space?
It’s very puzzling that the moon landing had no stars in the background, the ISS clips have no stars in the background. I listened to multiple astronaut interviews speak on what it looks like up in ...
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Data on galactocentric distances of various stars?
I'm creating a project for my astronomy class (introductory course) that requires knowledge of the galactocentric distances for many stars. I'm struggling to find a good source on this, and I'd rather ...
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Can any type of stars be contact binaries?
In this article Shortest distance between stars it is mentioned that
Some double stars can actually be in contact with each other.
This occurs when a red giant star has a white dwarf star ...
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How many arc seconds is Sirius "spiralling motion" around Sirius B?
I know that Sirius A and B orbit each other. I'd like to ask how large is their relative apparent motion in arc seconds, seen from Earth?
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What happens when a star gets hit by a supernova?
This may sound like a strange question, but say that two stars are relatively next to one another in a binary star system, what would happen to one of the stars if the other went supernova? Would it ...
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Recognising lunar month only by looking at the sky
Suppose somebody went on an island and don't have sense about time, dates, months. The only thing he has is seeing the sky. Is it possible to recognise which lunar month it is by just looking the sky?
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Do all orbiting objects have barycenters?
From the simple perspective of someone like myself, it appears that our sun is "fixed in place" (from the perspective of the solar system itself) and that everything else of lower mass orbits around ...
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What is the official classification and naming system of objects in the universe(, or what would my URI look like)?
Poetic human centric approach:
Universe/Laniakea/Virgo/MilkyWay/Sol/Earth/Humans/AndreasT
Little bit more technical:
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Where do gas giants end up?
I want to create a semi realistic star system generator but I am not sure where to "put in" gas giants. My guess is they can form pretty much anywhere within the sphere of influence of a star at the ...
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H-R diagram, Double stars
Can someone help me? I have a case, like, we have H-R diagram and two stars on it. One of them is a blue star on main sequence, another is a red giant. They have equal luminosity. If they are in a ...
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Trisolar syzygy and it's effects on the planet
Slightly spoilers here, but in the novel The Three-Body Problem, there's a scene in which Civilization #184 is destroyed by the stacked gravitational attraction of the planet's (aptly named Trisolaris)...
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Color changing celestial body near the moon [closed]
While I was star gazing yesterday in the night time I observed a celestial body( probably a star ) flaunting various colors and was residing near the moon from the angle I saw it. It appeared to be ...
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Spectrum of star
I constructed a telescope and fixed my mobile's camera to the eye lens. I then viewed the sky via the mobile and I captured this image.
This is the magnified version of it:
I'm not sure if this ...
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Star revolving a star [duplicate]
Are there any star system(planet system) where a star revolves around a star? Is it theoretically possible?
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What if a white dwarf is less massive than her partner?
For example: a system with a 0.2 solar mass white dwarf orbiting a 0.25 solar mass red dwarf. Does the red dwarf steals mass from the white dwarf or vice versa.
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Why are nearby stars like Proxima Centauri and Barnard's star not visible to the naked eye?
Proxima Centauri is the closest star to the earth other than the sun yet it isn't visible to the naked eye, but stars that are further away are easily found in the night sky. Why is that?
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What differentiates a "group of rogue stars" from a galaxy?
According to Wikipedia, a rogue star or intergalactic star is
not gravitationally bound to a galaxy.
But according to a citation on the same Wikipedia page, the first intergalactic stars were ...
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Could we see planets around active Stellar Mass Black Hole?
This question is a followup of Is there any theoretical or empirical research about planetary systems with a black hole in their center?;
Since it is possible to detect planets around stars with the ...
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How are solar systems found again after being discovered?
Discovering a solar system that cannot be seen by the naked eye on earth seems like an easy task with telescopes (e.g. the hubble telescope). I'm guessing, that our sun is the reference point for the ...
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Star systems forming when large gravitational force is applied
As far as I'm concerned, most star systems in our galaxy are traveling in fairly circular paths around the black hole at the center.
Hypothetically, if a large gravitational force pulled star ...
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Why does Sirius proper motion "wiggle" with a 1 year period, when Sirius A and Bs binary orbit is a 50 year period?
Some stars, if observed repeatedly over time, show a perturbation or "wobble" in their proper motion. If this is a periodic occurrence we can infer that the perturbation occurs due to the ...
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What is the tidal radius of the Sirius system?
The Fomalhaut system is a trinary system, with Fomalhaut A (1.9 M), Fomalhaut B (0.7M) and Fomalhaut C (0.2M). Fomalhaut C is 2.5 light years from Fomalhaut A, and 3.2 light years away from Fomalhaut ...
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Do you know about any Image Processing Challenges known in Space Telescope like Hubble?
For a computer science project in University;
I need to find image processing problems on space exploration and Space Telescopes, only related to the image itself.
I have wrote a computer program ...
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Why is the exoplanet HD 131399Ab so hot?
Recently, a fascinating triple-star system with an exoplanet has been discovered (arxiv).
I'm very surprised about the temperature of the exoplanet: it is roughly 850 kelvin, even though its orbit ...
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Can a star eject a liquid or a gas that has not been ionized?
Can a star eject a liquid or a gas that has not been ionized? I am implying that these gases could be a source of reusable energy.
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How many planets does Omicron Persei have?
Omicron Persei is a binary star. I did not find information on how many planets it has and if we can actually determine it currently. However, I do know that most stars have planets orbiting around ...
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