# Tagged Questions

The path a body takes while moving through space under the influence of the gravitational forces of other bodies

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### Meteor hitting the moon? [on hold]

Could a meteor hit the moon enough to cause a decay in its revolution around earth hitting the atmosphere causing molten rock to rain? I learned also the the moon was blasted out of Earth could that ...
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### Velocity of satellite to crash into the earth

I was reading through this post today and was very impressed by the response that was given. However, what would have to happen to the velocity in order to collide with the Earth? Velocity of ...
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### When do two point masses orbit or collide? [on hold]

Suppose we have a universe containing two point particles with possibly different masses and initial positions/velocities (with respect to some fixed reference frame). Neglecting relativity and ...
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### How can a polar orbit of a satellite be achieved? [on hold]

I mean an orbit in which the satellite is above antarctica on southern hemisphere and above arctic circle in northern hemisphere? I guess it won't be possible to be exactly above the axis but closer ...
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### How do gravitational sling shots work? [duplicate]

How can an object move faster after leaving the gravity of a planet, should a gain in potential energy by moving away from the planet lead to a loss of kinetic energy? Or am I missing something ...
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### Satellite collides with earth [duplicate]

Suppose we have a satellite in a circular orbit around the earth. We know that the velocity is given by $$v = \sqrt{\frac{GM}{r}}$$ I'm curious as to what conditions on a velocity change would require ...
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### Is the motion of rotation perfectly symmetrical? [duplicate]

Scientifically, can we say that one of these assertions is more "correct" than the other? (philosophically we can say that the first one is more correct because it makes the motion of other planets "...
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### Newton's law - satellite position (in 2D) for specific moment of time [closed]

I’m trying designate function that calculate satellite position (2 dimensional) for specific moment of time for better understanding Newton's law of gravity. To verify my calculations I created second ...
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### Find the mass of Europa, one of the Moons orbiting the Jupiter [closed]

Europa, one of the moons of Jupiter, was discovered by Galileo in $1610$. Europa has a circular orbit of radius $6.708\times 10^5$ km and period $3.551$ days. Find the mass of Jupiter. My attempt: ...
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### How to calculate transit time for a specific section of an orbit?

I've searched high and low and I haven't been able to find a formula for this. I'm trying to calculate the time it will take to transit through a defined arc length of an elliptical orbit, whose ...
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### Possible to redirect atmosphere lost to space back to a planetary body [closed]

So I understand that lower gravity planetary bodies tend to lose atmosphere at a pretty quick rate, and as I understand it when the gases break free they are blown away in the direction that the solar ...
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### Charged Accelerometer in Orbit

It is well known that an accelerometer (or any other object for that matter) in a gravitational orbit will register nearly zero acceleration. According to this answer, this is because the object is, ...
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### How does the Giant Impact Hypothesis resolve impulse for orbital insertion?

The Giant Impact Hypothesis describes that Earth's moon was formed from collision between a proto-Earth and another Mars-sized object. This collision ejected mass from the Earth into orbit, whereupon ...
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### Why don't we feel the subtle speed change of Earth's elliptical orbit?

Earth's orbit is a slight ellipse, so to conserve momentum its speed increases when it is closest to the Sun. If the speed changes there is an acceleration. If there is an acceleration there is a ...
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### Effective Potential in General Relativity

I would like to clarify a concept about the Effective Potential in General Relativity when the kinetic energy term is not unitary. Suppose (in spherical coordinates) one has a generic line element of ...
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### Change in gravitational effect between Earth and the Sun

SPOILERS FOR "INDEPENDENCE DAY: RESURGENCE" ABOUND. I just watch ID:R and had a question about a plot point. In the movie, a large alien ship, which looked to be about 10-20 percent the size of Earth ...
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### How can an asteroid fall to a planet?

According to the Kepler's first law, the orbit of an asteroid would be an ellipse having the planet at one of the focuses (to a good approximation). Then how come can it ever fall to the planet?
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### How to calculate the mechanical energy of a planet orbiting a Sun in a ellipse orbit? [closed]

I learned how to calculate the energy of the planet orbiting in a circle. then what about ellipse? I mean, why does the planet's energy is same when we model the planet's orbit into a circle which the ...
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### Juno probe's speed is in relation to what frame of reference?

When describing the velocity of space probes in general (the Juno probe in particular) what frame of reference is the velocity quoted in? This is in relation to the news of the Juno Satellite ...
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### What does the Moon's orbit around the Sun look like?

I'm curious as to what the Moon's orbit around the Sun looks like. If there's an answer, what's the intuition for it? Here are some things I'm assuming when trying to tackle this question: The Moon'...
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### Is it possible that an object orbits another object without ever tangenting or crossing its equator?

Imagine Object 1 beeing the earth and object 2 beeing the moon having a orbit around earth, like the yellow line is demonstrating. Could something like this anyhow naturaly as standalone occur? I'd ...
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### Maximum Angular Momentum for an orbit in GR

[The reference for this question is the book Gravitation by Misner,Thorne, & Wheeler.] The trajectories of massive particles around a spherically symmetric body is governed by the effective ...
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### How to calculate orbit of a sphere around a bigger one in microgravity?

I don't have any knowledge in physics, but in a world building related question, I need to know how can I calculate the orbit or the distance in each point of the orbit around a spherical object in ...
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### Why doesn't orbital body keep going faster and faster? [duplicate]

If we consider the change in velocity during an infinitesimal interval of an orbit: where body B is orbiting body A, we can see that the magnitude of the resultant vector (the green arrow) is ...
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### Orbital Velocity & LLR

As I understand it, light that is emitted from a source is not imparted with the motion of the source and so always follows a "straight line". If this is correct, I am having a difficult time ...
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### What is exact difference between gravitational force and magnetic force? [closed]

I've read that gravitational force is due to mass only and magnetic field is due to moving charged particles. But my question is: what are other difference between them? Can we set up a small ...
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### Keplerian orbits and radial velocities: problem with true anomalies

I am writing a pure Python code to calculate radial velocities of stars with massive objects orbiting them. I am following the formalism from Murray & Correia (2011) (hereafter MC11). In a given ...