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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Which star system has the highest multiplicity (# of stars), whose orbits are known for all stars?
I posed a question on here a couple months or so ago about the orbital patterns of each of the seven stars in the two septuple star systems Nu Scorpii and AR Cassiopeiae. It went unanswered for more ...
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How do the orbits of star systems V871 Centauri (septuple), Gamma Cassiopeiae (octuple), and QZ Carinae (nonuple) work?
Several years ago, I asked the question on here, "How do the orbits of Nu Scorpii and AR Cassiopeiae work?" At the time, these two stellar systems were the most populated (I don't know the ...
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Is the motion of Mercury circular when viewed from Earth?
If observed from Earth, the Sun appears to move in an approximate circular orbit. For the motion of another planet like Mercury if observed from the earth, would this be true? If not, why? What about ...
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How to translate from local laplace plane to ecliptic J2000 (or ICRF)
The NASA JPL websize gives mean orbital elements for e.g. Iapetus or Titan in relation to the local laplace plane.
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Apsidal precession
I found this article about calculating apsidal precession:
https://farside.ph.utexas.edu/teaching/336k/Newton/node115.html
I tried to calculate rate of apsidal precession from this equation, but I had ...
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Orbit of the moon so that there are no eclipses
Theoretically speaking, what orbit should the earth's moon must take so that there are never any eclipses - solar or lunar? Is it mathematically possible to construct such an orbit?
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Are there any bodies in the solar system whose rotation is almost tidally locked or barely tidally locked?
The Moon's rotation is firmly tidally locked to the Earth and the Earth's rotation is firmly tidally unlocked with respect to the Moon. I gather that Mercury's rotation is tidally locked in a 3:2 ...
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How to convert TEME (or ITRF) to horizontal
I have TEME coordinates from sgp4 propagation. I can convert those (in python) to ITRF given date and time of observation. How to convert coordinates from one of those two frames to horizontal azimuth ...
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What are "non-Keplerian" orbits? What are some familiar examples in our solar system, and can some still be closed?
This excellent answer to Forms of stellar orbits around the galactic center invokes the following concepts:
non-Keplerian orbits
closed orbits
I have a fairly good idea what these mean and so might ...
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Are dust-dust collisions necessary to explain Kordylewski clouds at Earth-Moon L4/5? Aren't the cross-sections, number density timescales too small?
The recent question Can dark matter accumulate at Lagrange points? mentions Kordylewski clouds and that article begins:
Kordylewski clouds are large concentrations of dust that exist at the L4 and L5 ...
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Under which conditions could a planet's massive moon's orbit get closer to the planet?
The recent question How do we know the Moon was much closer than it is now? has piqued my interest. The answers are numerous and clear. But I started to wonder. The question includes the following ...
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How to turn find velocity dispersion from radial velocity
In the above given picture Vi is the velocity of the i-th galaxy in the cluster while Vm is the mean velocity of a galaxy in the cluster. and V i,r is the radial velocity of the i-th galaxy and V m,r ...
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Concerning a binary system of stars/planets/black holes could one of them be ejected before eventually merging or colliding?
I was having a discussion with an undergraduate student of physics about binaries and their interactions with external celestial bodies (which could cause the ejection of one of the members in the ...
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Gravitational recoil with stars/planets...?
When two black holes are merging, the resulting merge can be ejected if one of the black holes had less mass than the other one, so the gravitational waves emitted by both of them is unbalanced, and ...
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Eccentricity of TLE orbit from velocity and radius in TEME
I was reading this question: Calculation of Eccentricity of orbit from velocity and radius and tried to use the proposed equation to reconstruct the ecco field of TLE by it's R,V vectors. The formula ...
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