# Tag Info

Accepted

### Why are asteroids with zero orbital inclination rare?

Short answer: The scarcity of asteroids with an inclination near zero is an expected result of normally distributed inclinations in 3-dimensions about the normal vector to the reference plane, rather ...
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### At what point are orbital resonances no longer "ordered" but "chaotic?"

Consider a child on a stationary swing. The fastest way to get them going is to push once every time they swing (a 1:1 resonance). If you push 581 times for every 137 swings, the pushes will mostly ...
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### What exactly was the Moon's "Evection Resonance"?

The orbit of the moon is elliptical. But the direction of the major axis of this ellipse isn't fixed. Perturbation by the sun causes the axis to rotate towards the East. The time for the moon to go ...
• 123k
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### Planetary orbital resonances

This is actually a very subtle question, much more so than the answers to the similar questions provided in the comments give it credit for. When I was in graduate school at Ohio State I routinely ...
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### How do tadpole, horseshoe co-orbital states arise and how are they stable?

If the body is in front of the planet (relative to the planet's orbital motion) and a little further from the sun, it will orbit the sun slightly slower than the planet. As it is slower, the planet ...
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### Orbital resonance and the precession of the periapsis

The revolution period of a body is the time it takes to return to pericenter. So, for example, Io will return to its perijove after 1.769 days, and Europa to its own perijove after 3.551 days. But ...
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### Why are asteroids with zero orbital inclination rare?

In spherical polar coordinates, one of the coordinates used is an angle between the direction to a point in space and a "pole". Let this "pole" be the ecliptic north pole and call ...
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### Could a Trappist-like planetary system exist around a sun like ours?

That is a fascinating question due to the fact that planetary orbits have both absolute and relative spacing. The absolute spacing between planetary orbits is the number of kilometers that the semi ...
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### Hypothetical planet jump: Will it perturb star systems?

There is essentially no room in our habitable zone for another Earth-sized planet. The exact timescale for instability would depend on the details of where you put it, but the system couldn't survive ...
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### How do higher numbers affect orbital resonance?

General Explanation In the history of our Solar System, the orbits of Solar System bodies have gradually evolved, passing through many "higher number" orbital resonance ratios. Only the ...
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### Are there other possible Laplace resonances? (e.g. 1:3:9)

The Wikipedia article you linked contains several other examples, both in our own Solar system, e.g. 18:22:33 for some of Pluto's moons, as for exoplanets. There are all kinds of ratios to be found (...
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### How do tadpole, horseshoe co-orbital states arise and how are they stable?

How, when approaching the planet, does the body "fall behind" instead of continuing to accelerate toward the planet? This is fundamentally the gravity assist problem. In the 2 body system, the ...
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### Explanation of resonance stability and instability

Mercury and Spin-orbital resonance is pretty straight forward. Planets and Moons are gravitationally lumpy and large bodies are somewhat fluid, even rocky bodies. Both aspects are prone to tidal ...
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### Is this a stable system?

Seems like it would be subject to Kozai oscillations at least-- see https://www.cfa.harvard.edu/research/ta/kozai-lidov-mechanism. That mechanism tends to swap obliquity for eccentricity, without ...
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