Questions tagged [orbital-motion]
The path a body takes while moving through space under the influence of the gravitational forces of other bodies
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Orbit description in Schwarzschild metric
Suppose to have a restricted 2-body system (BH + star with $M_{BH}\gg M_{\mathrm{star}}$) and you want to describe the orbit of the star relative to the BH, i.e. in the Schwarzschild metric.
Usually, ...
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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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How to find the length of a travel between planets using the Hohmann Transfer?
I am trying to figure out how long it would take to get from one planet to another. This is for a worldbuilding project of mine. I would put my question on the Worldbuilding Stack Exchange but I ...
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Average Speed in one half of an elliptical orbit
I was wondering whether the average speed along one half of an elliptical orbit (say in a star planet system) had a closed form exact solution using Kepler's laws.
My approach was using the ...
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When is an object no longer considered orbiting a celestial body during its descent?
During the Apollo mission, once the LM began its descent to the surface of the moon, was it still in orbit about the moon?
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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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Speed at which the Moon moves past a point on Earth's surface?
I'm trying to calculate how fast a point on the surface of the Moon is moving past a point on the surface of the Earth (I assume a point on the equator of each for simplicity).
I know the Earth is ...
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What is the locus of the velocity vectors of a spaceship moving in some distance from a black hole?
Someone with a background in mathematics and limited knowledge of physics asks the following question:
Starting from rest, a spaceship is momentarily pushed with a specific amount of kinetic energy in ...
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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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Kepler orbit from mass, period, and eccentricity [closed]
I want to calculate the Keplerian orbital elements in the central force case.
Given the mass M of the "sun" in kg, the eccentricity $e$ of the orbit, and the period $T$ in seconds, I believe ...
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Applying 1 gram-force for 1000 seconds to 1kg mass
I am looking into ion thrusters and the small amount of propulsion they provide.
I am really new to this, so I want to understand. If we have mass of 1 kg in space and we are able to apply to it a 1 ...
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Approximation of Nearly Circular Orbit by a Precessing Ellipse
I am self-studying the 3rd edition of Goldstein's Classical Mechanics and have hit a roadblock when working a problem (Chapter 3, Problem 20). The problem asks us to consider a planet of mass $m$ ...
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Orbiting body around a star
Let us assume there's a body with mass $m$ and velocity $v$, at a distance $r$ from another body of mass $M$. The velocity vector is perpendicular to the radial vector. With these values, how do we ...
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What is the name of this pendulum? [closed]
What is the name of a pendulum with two parallel string hung vertical to a rod, and giving the rod an initial force would make it swing left and right, doing simple harmonic motion?
What is the ...
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Parabolic(?) projectile orbits as an approximation to elliptical orbits given a rotating Earth
Why is projectile motion a parabola given that the Earth rotates and a parabola is an approximation to an orbit.
My current thought is that projectiles don't travel in a parabola because if the Earth ...
