Questions tagged [orbital-mechanics]
The application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets and other spacecraft.
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Are the Trappist-1 planets in stable orbits?
The Trappist-1 planets all orbit very close to each other. During NASA's press release, they mentioned that these planets are close enough to disturb each others orbits. Is this system stable over a ...
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What is $\phi '$ in orbital mechanics?
For the last week or so, I have been teaching myself orbital mechanics within the context of Braeunig's Rocket and Space Technology.
I noticed a symbol, $\phi '$, and was wondering what context that ...
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On orbital mechanics of evaporating planets
A planet orbits around its sun on an elliptic orbit, and loses mass slowly due to evaporation. How will the parameters of the orbital ellipse change as a function of time?
Could we do a generalisation ...
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What is the shape (along the plane, not up-down) of stellar orbits in flat spiral galaxies
What I mean is, with a central mass orbits are relatively simple, but orbits around the galaxy are different, in essence as the star orbits through the dark matter halo, the further it moves away from ...
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J2 perturbations and orbits
I am trying to solve a problem where I need to calculate a satellite's orbit, but first I would like to ask for some clarifications from someone here that might know this stuff. I need to design an ...
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Have any co-orbital exoplanet pairs been discovered (and not subsequently retracted)?
For this question, I think a good working definition of co-orbital configuration would be two bodies orbiting around a third much larger body in a 1:1 resonance and where neither mass is negligible. ...
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Calculate eccentricity with altitude and semiminor axes
Following on from this question, I wish to know how to find the reverse - how to find eccentricity given a Semi-minor axis & altitude.
I want to use something based on
$$b=a\sqrt{1−e^2}$$
but ...
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Effects of the solar tide on planets
It’s well known that (lunar) tides on Earth result in a transfer of angular momentum from Earth proper to the Earth–Moon orbital motion. That’s why the Moon resides now in a high Earth orbit, and ...
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Intercept a NEO trajectory
I need help with an exercise in the book that I can't tackle. I need to calculate how much time we have to intercept and eliminate a NEO. I got the following orbital parameters:
a=-2791.44 km (semi-...
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Binary stars of different ages?
In an answer on a different SE someone raised the point that “common” explainations published never discuss stars being captured. Presumably binaries are formed as pairs, or team up while still in ...
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What is the most asymmetric known planet?
Planets are more or less spherical, can you tell which one is the most asymmetric? Do they figure out such a property from an eccentric behaviour, or what?
I have a simple technical question: an ...
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Is the radius used in the formula for the escape velocity the average radius of the celestial object or the radius at the starting location?
I learnt that the escape velocity is given by $$v_e = \sqrt{\frac{2GM}{r}}$$
Say I want to launch a rocket from the earth into space and want to calculate the escape velocity $v_e$ (I guess without ...
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Will Gaia detect inactive neutron stars?
Will the astrometric precision of the Gaia space telescope be able to detect the gravitational influence of cold old solitary neutron stars on the movements of stars? At least in a statistical sense ...
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The Three Elements in the Milankovitch Cycles
According to the Serbian geophysicist Milutin Milankovitch, there are three elements that make an ice age possible:
Eccentricity (orbital shape): Varying between 0.000055 and 0.0679 over the course ...
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Distance and orbital period for terrestrial binary planets
This article, http://phys.org/news/2014-12-binary-terrestrial-planets.html, suggests binary planets could orbit each other at a distance of only three planet radii. For two earth-like planets, that is ...
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