The celestial-mechanics tag has no wiki summary.
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Parallax, obliquity, precession, and Orion?
Today, the obliquity of the earth is about 23.4°.
6500 years ago, it was about 24.1°
Imagine the blue square is the constellation of Orion, and the yellow star is the sun. Viewpoint B is you, on ...
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1answer
101 views
Does the possibility of large scale entanglement mean 2-Body Problems are also unsolvable?
Experiments are showing that larger and larger objects can be entangled whereby proving that this quantum feature has no upper limit. Assuming this is true, does entangled celestial bodies mean even ...
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Planets motion around the sun [duplicate]
Why planets of solar system move almost in the same plane?
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1answer
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Relation between satellites' potential energy and quantum mechanical confinement energy?
The energy of a single planet in a gravitational potential is $$E=\frac{m\dot{r}^2}{2}+\frac{L^2}{2mr^2}-\frac{GMm}{r}$$
And the effective potential energy is defined as the last two terms. Note this ...
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261 views
Speed of the Moon
Why the motion of the Moon looks very slow in the sky? Doesn't it need the high speed in order to escape the earth's gravity?
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Falling through the rotating Earth
Suppose you were standing on the rotating Earth (not necessarily Equator or the poles) and suddenly your body lost the ability to avoid effortlessly passing through solid rock.
Because the earth's ...
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2answers
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Can an orbit be calculated using two points and transit time?
Working in only two dimensions and assuming that the central body is at the origin of the coordinate system, given two points in space and knowing the transit time between those points, as well as the ...
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1answer
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Potential Energy tends to infinity on the N-Body Problem
I need help to solve this problem related with the N-Body problem, i dont understand quite well what I need to define or to express in order to solve it.
We assume a particular solution to the N-Body ...
6
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2answers
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Is there any dynamical reason for the winter solstice to happen close to the perihelion?
When the winter solstice arrives, the angular momentum of the Earth, its orbital angular momentum and its radius vector with the orbital focus in the Sun are in the same plane. This happens quite ...
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Do black holes accelerate in spin as they obtain more mass?
It is known that - When a star collapses during the formation of the black hole, the black hole obtains the spin of the star which it collapsed from...
What I'd like to know is, If this spin ...
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2answers
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How to learn celestial mechanics?
I'm a PhD student in math and am really excited about celestial mechanics.
I was wondering if anyone could give me a roadmap for learning this subject. The amount of information about it on the ...
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Is it feasible for an unmanned vehicle to travel from outside the atmosphere of one planet to another without additional propulsion?
Within the Solar System (or any other system for that matter) -
Is it feasible for an unmanned vehicle to travel from outside the atmosphere of one planet to another without additional propulsion? ...
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1answer
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What parameters determine the acceleration a spacecraft can acquire using the gravity of a celestial body?
Contemporary spacecraft frequently rely upon gravity to accelerate/decelerate.
Given a spacecraft already in space - What factors determine the acceleration it can acquire from the gravity of another ...
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1answer
190 views
Angular momentum components as independent integrals of motion
I was told that in order to solve the Kepler problem (6 degrees of freedom in total) you have to proceed, step by step, to reduce those degrees of freedom using the integrals of motion. You do so ...
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1answer
128 views
What is the typical orbital life of an artificial satellite?
The orbit of satellites around Earth eventually decays, or so I read. This is typically caused either by atmospheric drag, or by tides. I would assume most satellites have a limited service life in ...
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0answers
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Simple model of the solar system. Parameters? Accuracy?
I was thinking of making a simple 2D model of the solar system, with planets moving along ellipses like
$$x(t) = k_x \sin(t + k_t) (\sin(k_\phi) + \cos(k_\phi))$$
$$y(t) = k_y \cos(t + k_t) ...
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5answers
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Gravitation in a space that is topologically toroidal
In my scant spare time I'm building an Asteroids game. You know - a little ship equipped with a pea shooter and a bunch of asteroids floating around everywhere waiting to be to blown up. But, I wanted ...
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1answer
226 views
On the origin of the rotation of celestial bodies [duplicate]
Possible Duplicate:
Why does Venus rotate the opposite direction as other planets?
Why does every thing spin?
As far as I can imagine, almost each celestial body, star, planet, ...
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3answers
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the collision of Phobos
Mars has two moons: Phobos and Deimos. Both are irregular and are believed to have been captured from the nearby asteroid belt.
Phobos always shows the same face to Mars because of tidal forces ...
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6answers
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Why is the universe so organized?
If you think about the Big Bang and the flow of matter in all directions, you would think, how unorganized would this universe be? No matter how long it would take. The idea that matter or most of it ...
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4answers
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Can a moon have another large body as a satellite, and are there any examples of such?
In my mind, I'm comparing it to the Sun-Earth-Moon system. After all, the Earth is primarily a satellite of the Sun, but the Moon is still gravitationally bound to the Earth. Could something like this ...
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2answers
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What did general relativity clarify about Mercury?
I frequently hear that Kepler, using his equations of orbital motion, could predict the orbits of all the planets to a high degree of accuracy -- except Mercury. I've heard that mercury's motion ...
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Calculation of a Gravity Resonance Keyhole
Can anyone describe the mathematics behind the calculation of a resonance keyhole (for a two-body model)? It seems like the size and position of the keyhole should be a function only of mass and ...
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2answers
533 views
How do horseshoe orbits work?
An asteroid was recently discovered that is in a horseshoe orbit with respect to the earth. Is there an intuitive explanation for these orbits? It seems that the earth acts as a repulsive force where ...
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3answers
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How accurately is the moment of perihelion of Earth known, and how is it measured?
Earth's perihelion passed about nine hours ago. How accurately do we know the moment of closest approach of the Earth to the center of the sun? How do we make this measurement?
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Why are the orbits of planets in the Solar System nearly circular?
Except for Mercury, the planets in the Solar System have very small eccentricities.
Is this property special to the Solar System? Wikipedia states:
Most exoplanets with orbital periods of 20 ...
