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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Extreme Mass Ratio Inspirals and GWs cycles
I was reading through the following paper GRMHD study of accreting massive black hole binaries in astrophysical environment: A review. Therein, we have the following image
It is not quite clear how ...
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Do we use transit photometry to look for a black hole star binary systems?
What would a light curve look like for a black hole transiting a star? Initially I thought it would bend all light essentially blacking out a star but we would probably still detect some however the ...
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How to relate a gravitational plane wave to the GW from a binary system?
I have two different forms of gravitational waves that I am trying to reconcile.
A monochromatic GW with angular frequency $\Omega$ propagating in the $\textbf{n}$-direction can be expressed as
$$ ...
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Where can I access spectra shift data on a given binary star?
I need to access spectra shift data which I can use to plot a radial velocity of a binary star vs time graph for an assignment.
I have looked at SDSS and I havent had any luck being able to access ...
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Where can I find spectra data and light curves of a stereoscopic binary star system?
I am trying to find a suitable source of spectra data and/or a light curve of a binary star (no exact star in particular), with which I would use to find velocity and period, and then find masses etc.....
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Impact Parameter as function of orbital parameters
In the case of a binary system (pulsar+companion), the impact parameter $\textbf{b}$ is the projection of the binary separation $\textbf{r}$ on the sky plane:
\begin{equation}\tag{1}
\textbf{b} = \...
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How close does a dwarf star have to be to remove the corona from its neighbour in an elliptic binary system?
It is possible for a larger (wider, but less massive) star to mutually orbit a heavy dwarf companion star in a binary system. If the dwarf star gets close enough it can attract the corona of the ...
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Confusion about Post-Newtonian orbital motion (Damour-Deruelle)
In their famous paper in 1985 (link), Damour&Deruelle describe the orbital motion for a binary system taking into account first-order post-Newtonian corrections (1PN). The solution is given in ...
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Would there be one rainbow, a double rainbow or bisecting rainbow on a planet with two suns?
I'm just curious if binary stars are low over the horizon and the conditions are just perfect for the formation of rainbow, would I see a single rainbow, double rainbow or two rainbows intersecting ...
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Inquiry Regarding Hypothetical Celestial Mechanics Scenario
How would the addition of a second sun, located at the other focus of the planet's elliptical orbit, impact the motion and orbit of the planet? Specifically, how would the gravitational forces from ...
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Stress-Energy Tensor for a Two Mass System
I just don't understand this tensor and would like to go through an example with you to somehow make sense of it.
I consider two spheres with masses $m_1$ and $m_2$, densities $\rho_1$ and $\rho_2$ ...
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Hills Mechanism
The Hills mechanism postulates that when a stellar binary system is perturbed by a supermassive black hole (SMBH), the tidal forces at play result in the capture of one star while simultaneously ...
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Can we correctly invoke energy conservation to explain why binary systems do collapse in GR?
I've learned that binary systems emits gravitational waves, so there is energy leaving the system in the form of waves and so the radius of the binary system must decrease as to maintain the ...
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Could two rotating binary neutron stars create massive cosmic rays if their magnetic fields overlapped and acted on a volume of gas?
The so-called GZK cosmic rays sometimes have an energy equivalent to a baseball moving at 30 m/s.
The source of these rays has yet to be determined. Could 2 rotating neutron stars orbiting one ...
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GENERAL RELATIVITY: gravitational time dilation outside 2 bodies [closed]
I know that gravitational time dilation near a single body is:
$$T_2=T_1\sqrt{1-\frac{2GM}{rc^2}} $$
Can you give gravitational time dilation formula when in proximity to multiple bodies?
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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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