Questions tagged [binary-stars]
Binary stars are a system of two stars rotating around their center of mass, as opposed to single stellar systems such as our solar system.
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General relativity: The metric outside of $n$ static bodies [duplicate]
I know that the space time metric outside of 1 static body is the Schwarzschild metric. can anyone tell me what is the metric outside of 2 static bodies or 3 or more static bodies? (' static ' mean ...
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How line of sight is determined?
How do they calculate the line of sight of a galaxy or binary star system from an observer's point of view. the velocity of a star in a binary star system depends on the line of sight so how do they ...
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Orbital phase and gravitational wave phase
I am trying to understand the relation between the orbital phase of binary and the phase of the gravitational wave when expressed as spin-weighted spherical harmonics.
The metric perturbation can be ...
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Star with quadrupole in binary system violates Newton's 3th law?
Suppose that, in a binary system of two stars, the star A (and only the star A) has a non-zero quadrupole moment $Q_A$. Then, the star B feels the usual gravity force plus an additional force, ...
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Methods for calculating the orbital speed of a star in a binary system
As I understand it, to calculate the speed of rotation of a star in a binary system that is receeding, that is in the same plane as us (inclined at 0 degrees) the method is use the Doppler formula: Δλ/...
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Problem in an ellipse circumscribed on an auxiliary circle
I was reading the book "an introduction to the evolution of single and binary stars", by Mattew Benacquista, and I couldn't understand a specific step in topic 2.1 (Time-Depedent Orbits), ...
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Meaning of Left-Right Arrow in a Fitting Formula [duplicate]
I initially posted this question on Astronomy Stack Exchange but the site seemed rather inactive so I will try to ask it again on Physics, hopefully it doesn't go against any rules.
I was reading this ...
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Temperature estimate from eclipsing binary
So assuming perfect edge on eclipsing binary, we can estimate the temperature ratio of the two stars because the "blocked area" is the same, and thus the amount of light "dimmed" ...
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Does a double star system have more mass than its constituents?
According to Einstein, energy is equal to mass. Consider a planet that is in gravitational attraction to two stars. Normally I would say that the gravitational attraction is proportional to the masses ...
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Closest possible orbital radius for equal masses
If you have two objects of equal mass, then what’s the closest distance that they can orbit at in terms of their schwarzschild radii? How fast would they be orbiting?
What About stable orbits?
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If two black holes orbit around each other should their tidal forces cause a shrinking of the closer parts of their event horizons?
I recently asked a question about the influence of external gravitational fields on the stability of the geometry of a part or all the event horizon of a black hole. I understood the answer in a ...
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Approximation concerning gravitational waves from binary neutron star
I'm interested in studying two neutron stars orbiting each other and producing gravitational waves. In textbooks the calculation for the power of the radiation is done by considering the neutron stars ...
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Are there any binary red supergiants?
I wonder if we ever have identified or observed a pair of binary stars (red supergiants).
And I also wonder what would happen if they exploded, (theoretically) as we havent observed it. Also, would ...
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Does the Centre of Mass of a binary star system accelerate?
At the COM of a binary star system (where both stars has a different mass), the net force at the centre of mass is non-zero.
Does this mean that the COM will be accelerating? And if so, wouldn't the ...
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Can orbiting point masses precess?
In a recent Science News, it mentioned two orbiting black holes (which later combined) were precessing; i.e. their motion did not remain in a stable plane, but rather the plane itself was changing. ...
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