All Questions
Tagged with celestial-mechanics planets
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Shape of planetary orbits
What makes Venus' orbit almost circular, though mercury's is highly elliptical,even though it is closer to sun ? Further, Why is mercury's orbit most elliptical right after Pluto ?
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Is it possible to find the mass of a planet and its moon from only their diameter and the distance between them?
For example, a planet has a diameter of 200,000 km and its moon has a diameter of 20,000 km, the distance between them is 100,000 km. Would it be possible to find their masses?
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Would it be possible to pull Mars and Earth closer each other?
The burden of travelling between Mars and Earth comes from the distance. If the planets were closer, life could spread to Mars more easily, ensuring the survival of the intelligent lifeforms. What ...
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How deep does a gravity well need to be to remove particles from a planetary body?
I almost considered asking this question on WorldBuilding, however I wanted the brute mathematics on the subject, so please excuse the theoretical nature of this question.
I understand the basic ...
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Would a celestial body in a horseshoe orbit be tidally locked to the planet?
A smaller celestial body like a moon or an asteroid can be in a horseshoe orbit around a planet.
Since it might go inside the tidal lock radius (but does not stay inside it all the time), during the ...
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Gravity effects when deleting stars or planets
In one of the latest SCIFI movies, they collect a star absorving it entirely in a kind of planet size gun/machine. As mass cannot disappear, I assume it was just concentrated inside their machine (...
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Angular Momentum and Kepler's Second Law
Let me preface by saying that I get the gist of the conservation of angular momentum, at least qualitatively. To better illustrate my question, I will consider the case of a planet orbiting a star.
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Was Leverrier-Adams prediction of Neptune a lucky coincidence?
According to historians both Adams and Leverrier used Bode's law to guess the distance to Neptune, which led to a vast overestimation of its orbital period (Adams - 227 years, Le Verrier - 218 years, ...
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Planetary alignment of the gas giants?
There is this nice and new applet of the orbits of the planets around the sun:
Solar System Orrery
You can click and drag any planet and watch their relative orbits evolve in time. I was curious ...
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Elliptical path of planets [duplicate]
Why are the planet's orbits in the form of an ellipse and what is the proof that earth moves in an elliptical path with the sun at its foci? Initially it was thought that earth moved in a circular ...
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Why are planets in unstable equilibrium in a stable orbit? [closed]
It is well known that a planet in stable orbit is in unstable equilibrium. If e.g. the moon was just a few m/s slower in velocity, or a few m closer to the earth than it is, the gravity would ...
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Could this planetary superalignment happen?
Here's the 'superalignment' I'm referring to:
We've all heard the stories about 'mystical planetary alignments' that will increase/decrease the effective surface gravity experienced on Earth (one ...
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Tidal locking of a planet to a satellite
As in the case of Pluto and its moon Charon, both the bodies are tidally locked to each other, will the Earth ever be tidally locked to the Moon? Is there any effect on the rotation of the Earth ...
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Rocky Planet in the center of System [duplicate]
We all know that mostly stars are at the center of planetary systems, but is it possible that instead of a star there was a rocky planet in the center with stars (and other planets and moons) orbiting ...
user45974
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Binary Star system with one star stationary?
Can a Binary Star system be possible where in one star is stationary and the other star revolves around it? (Just like a planet revolving a star. i.e planets in the system and the star revolving ...
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