All Questions
Tagged with newtonian-gravity celestial-mechanics
373
questions
4
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1
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3k
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What would it be like if we had a planet very close to us?
My desktop background rotates through a bunch of space and nature scenes, and this one came up.
What would be the effect on people walking around down here, if another earth was looming overhead ...
- 257
53
votes
9
answers
23k
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Why are $L_4$ and $L_5$ lagrangian points stable?
This diagram from wikipedia shows the gravitational potential energy of the sun-earth two body system, and demonstrates clearly the semi-stability of the $L_1$, $L_2$, and $L_3$ lagrangian points. The ...
- 3,241
3
votes
1
answer
940
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 ...
- 4,723
26
votes
7
answers
87k
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Gravity on the International Space Station
We created a table in my physics class which contained the strength of gravity on different planet and objects in space. At altitude 0 (Earth), the gravitational strength is 100%. On the Moon at ...
- 363
9
votes
1
answer
489
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Orbit through L4 and L5
I was reading the Wikipedia article on Lagrangian points and doing the requisite wiki walk through the various quasi-satellites of Earth when a question occurred to me:
Could there be a stable or ...
4
votes
5
answers
1k
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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 ...
- 897
1
vote
2
answers
2k
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Do all planets rotate around the sun with the same acceleration?
I have this question in mind. suppose if by any chance, all planet around sun stopped rotating. then as per formula F= M * A. all planet should fall with same acceleration towards sun and ultimately ...
- 29
1
vote
1
answer
1k
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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, solar-systems, ...
- 1,436
9
votes
1
answer
680
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Will Neptune change Pluto's orbit some day?
My seven-year-old son loves astronomy-- so much so that we read space books before bed time. One of our books talks about Pluto's orbit crossing over Neptune's orbit and will be (or is) closer to the ...
- 550
5
votes
1
answer
287
views
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 ...
- 51
8
votes
5
answers
984
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Why aren't all rocks in space orbiting bigger rocks?
Why do only big rocks (planets) have satellites, and not small ones? Why doesn't cosmic dust orbit rocks that are many times heavier than the dust grains? If dust is still too heavy then what about ...
- 1,445
5
votes
2
answers
7k
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Measuring acceleration of Earth due to its fall around the Sun
Every orbiting of a satellite around a mass is nothing else but a constant fall - and therefore acceleration - towards this mass. In a way it is a "falling around" that mass.
My question Is it ...
- 3,711
7
votes
3
answers
2k
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How about an exact solution for the position of a planet as a function of time?
Recently I was surprised to discover that no exact solution for the position of a planet as a function of time exists. I am referring to the two-body problem in a gravitational field where Newtons law ...
- 6,841