Questions tagged [stellar-dynamics]
Questions about the branch of astronomy that studies the regularities in the motions of stars in gravitational fields of stellar systems, as well as the evolution of stellar systems.
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Does the Final-Parsec problem apply to stellar collisions?
The final parsec problem describes the difficulty of two blackholes merging with one another when their distances reach ~3.2 light years apart. Does this also then apply to stellar collisions, perhaps ...
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Direction of precession in epicyclic approximation
In an axisymmetric potential, if we denote the vertical (z direction) epicyclic frequency as $\nu_z$ and the guiding centre angular velocity as $\Omega$, then the rate of nodal precession is
$$
\...
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What would be the new Equation of motion if the magnetic field's origin is shifted from the origin of a co-rotating spherical polar coordinates?
The equation of motions due to the dipole magnetic force of a planet in a frame corotating with the planet and origin at the centre of planet assumed to be sphere components wise are given as below:
\...
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If a cluster of stars in dynamical equilibrium falls into a much larger blob of dark matter, will it get hotter and expand? Will it stop?
This question is inspired by ProfRob's inspiring answer to Are there really confined Globular Clusters? in which he invokes the concept of "virialization" where a dynamical system reaches ...
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Can our solar system ever be farther than Rigel from the center of the galaxy?
Old time science fiction stories often used the names of well known stars. Even though the few dozen stars which are well known to readers on Earth are only an extremely tiny fraction of all the ...
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Dynamics of red giant hydrogen shell
From what I understood from this answer to How can a red giant grow so big?
But this is not at all the way the shell fusing in a red giant self-regulates its fusion rate-- it cannot regulate its ...
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What does this tweeted Astronomy Plot of the Week mean? What does it represent?
Twitter user BenneHolwerda (@BenneHolwerda) recently tweeted August 10 Astronomy Plot of the Week:
And I think @SabineBellstedt and @_jessthorne summary graph deserves a spot for sure.
If you work ...
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Is this paper on globular cluster stability still up to date?
I'm looking to better understand the stability of globular clusters for an n-body dynamical simulation, specifically with respect to initial data conditions.
I know that the total potential energy ...
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How is phase defined in a binary orbit with eccentricity?
Are orbital phases of the black spot in the figure measured from some angle or time/period?
Usually, how is phase=0 defined? It is relative to the line of apses perhaps with phase=0 at periastron?
Any ...
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Do low-mass red giants last longer than high-mass red giants?
It turns out that red giant stars are not defined by uniform mass. Some can be only one-third as massive as our sun, whereas others can be eight times as massive. So I'm calling the both sides "...
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Deriving the first moment of Collisionless Boltzmann Equation in Spherical Polar Coordinates
I am following these notes: Dynamics and Astrophysics of Galaxies.
After equation 6.37, we have:
\begin{equation*}
p_r\,\frac{\partial f}{\partial r} + \frac{p_\theta}{r^2}\,\frac{\partial f}{\...
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Do the axes of rotation of most stars in the Milky Way align reasonably closely with the axis of galactic rotation?
The axis of rotation of the Solar System makes a large angle of about 60 degrees relative to the axis of rotation of the Milky Way. That seems unusual - for example, most of the bodies within the ...
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Binary star system effects at the barycenter
I haven't been able to find anything on this so far. Using Alpha Centauri as the study, what events/effects ( if any ) would happen between the two stars? More specifically, between the gravitational ...
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Has the plasma amplification of electromagnetic waves in solar type-III bursts (or otherwise in stars) been explored further?
This answer to the SciFi SE question In the novel The Three-Body Problem, does the Sun's amplification of radio transmissions have a scientific basis? cites a 1995 paper published in Chinese Astronomy ...
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Dynamical modelling of galaxies with counter-rotating components using the Schwarzschild method
I am currently trying to understand dynamical modelling using Schwarzschild's method. I have been doing some reading the past days, but I suspect that I am getting something really wrong. According to ...
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