All Questions
Tagged with orbital-motion celestial-mechanics
561
questions
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Has our knowledge of astrophysics and gravity reached the point where we can accurately calculate Lagrange points?
is it possible for us today given the knowledge we possess of gravity and our success with inserting satellites in to steady/ geosynchronous orbit and any knowledge we have on the relative size (and ...
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31
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Restricted 3-body: one large mass and two smaller ones
A restricted 3-body problem is usually understood as two large bodies and one much smaller one that doesn't affect the motion of the other two.
I am curious about a 3-body problem with one large body, ...
6
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7
answers
1k
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What changes the velocity perpendicular to radius in an elliptical orbit?
I'm working currently on a problem that asks to justify that angular momentum and kinetic energy conserves for a planet in an elliptical orbit. Although I've been taught that angular momentum should ...
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1
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61
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Find eccentricity of orbit given the velocity and the semi-major axis
Is it possible to calculate eccentricity of orbit knowing only the semi-major axis and the velocity of both celestial bodies? If not, what other additional information is required.
Does the fact that ...
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1
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44
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The magnetic force between the earth and the sun
There is a magnetic field around the earth and a stronger one around the sun. I guess there should be a magnetic force between the sun and earth. Now, shouldn't we take the magnetic force into account ...
2
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37
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When are two object guaranteed to keep getting further and further away?
In a two-body problem, it is known (if I understand correctly) that if the specific orbital energy of the system is $\varepsilon \geq0$, then the objects must eventually escape each other. My question ...
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Speed of satellite in elliptical orbit [closed]
A satellite $S$ orbits a planet of mass $M$ in an elliptical orbit. At perihelion, $S$ has a tangential velocity of $v_1$ and is distance $r_1$ from the planet. At aphelion, $S$ has a velocity of $v_2$...
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81
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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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2
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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 ...
1
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0
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28
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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 ...
2
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2
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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 ...
1
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Two bodies orbiting around barycenter
There are two bodies with masses $m_1$ and $m_2$ orbiting around barycenter. Distances to both bodies from barycenter are $r_1$ and $r_2$ . First body has known velocity $v_1$ as on the picture :
My ...
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How does moving the pericenter affect the apocenter?
A perfectly circular orbit of a constant height (distance from the center of mass of the orbited planet) around a perfectly spherical planet with smooth surface and no gravitational anomalies will ...
1
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1
answer
54
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Is there a way to use the distances of the two opposite apsides to determine the eccentricity of an orbit?
Is there a way to use the distances of the two opposite apsides to determine the eccentricity of an orbit? The ratio between the distances (i.e. perihelion & aphelion) seem like they'd have a ...
4
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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 ...