Questions tagged [orbital-motion]
The path a body takes while moving through space under the influence of the gravitational forces of other bodies
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Does an asymmetric top return to its position, while rotating in space?
For body rotating freely in space, How it's possible that the angular momentum in the rotating frame returns to its original position relative to the axes of the body, but the body itself, does not at ...
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Ptolemaic system parameters
I recently learned about the Ptolemaic system, which seems pretty accurate. There is even a simulator on the Internet: https://astro.unl.edu/naap/ssm/animations/ptolemaic.html
You can see that there ...
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What is the relation between Earth's orbit and orbit of another planet around Sun? [on hold]
Lately, I come across the following problem,
"The maximum and minimum speeds of a comet that orbits the Sun are 80 and 10 km/s respectively. The ratio of the aphelion distance of the comet to the ...
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Conservation of volume in phase space: origin of the Moon
Here are two snippets from the Washington Post on the origin of the Moon:
Me:
We now know of a new braking mechanism that makes a Capture theory of the Moon's origin more persuasive. As the Moon ...
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1answer
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Show that angular momentum is independent of the angle
I was thinking about the Bohr atomic model which states, that the angular momentum (L) must be an integral multiple of the reduced Planck constant, this implies that $L=mvr$ must be constant for a ...
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Newtonian geodesic equation in barycentric frame
In a paper I was reading, I came across the Newtonian geodesic deviation equation
$${\ddot{\eta}}^a + K{^a}{_b}{\eta^b}=0$$
Where $\eta{^a}$ are the components of the 3 -vector separating the two ...
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2answers
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How does spatial curvature apply to the planets' orbits?
We all know that in the presence of large, massive objects, spacetime is positively curved, more so the more massive it is. This means that the path of an object without any forces on it is a straight ...
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How is spacetime warped by a massive object?
I was going through this question (Why don't planets have Circular orbits?) related to planetary orbits. In the accepted answer it is stated that orbits are actually conic sections.
Given this ...
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Which orbit planet will take with 2 stars?
Is there a law or an equation that shows which star gravity will win and suck a a planet that has 2 stars
Assume planet P has 2 stars A & B
A is smaller than B
Planet P is closer to A more than ...
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What does it mean that no two electrons with the same spin can occupy an atomic orbital?
First of all my notion of orbitals was that they are nothing more than the path traversed by an electron and more that it is the wave of the electron spread around the nucleus .
So going by that ...
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Is the white sky of Stephanson's novel “SevenEves” plausible?
Based on comments, would the moderators please move this to Astronomy.SE?
In the novel, some agency disrupts the moon. The moon is left in 7 major chunks that are still gravitationally bound. (...
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Orbit with constant central force
if a central force doesn't depend on the radius, its length is constant during moving.
I saw what its orbit looks like on Youtube: https://www.youtube.com/watch?v=sN_9_E-5sPA.
It seems that there are ...
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Throwing something into orbit [duplicate]
is it possible with newtonian gravity to throw something (which has no on-board propulsion) so that it will orbit the earth without colliding with it(friction is not present)? my intuition tells me ...
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1answer
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Torque and angular acceleration in elliptical orbit
I am stuck in a supposedly simple aspect. Consider the Sun-Earth system. The torque is zero and angular momentum is conserved. $L = I\omega$ is constant, but since $I$ changes, $\omega$ should change ...
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Is there a maximum distance from a planet that a moon can orbit?
Given a planet that orbits a star, and a moon that orbits that planet, is it possible to define a maximum orbital radius of that moon, beyond which the moon would no longer orbit the planet, but the ...
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Orbital stability and inverse square law
It is well-known that orbits are stable under an inverse square law gravitational attraction. My question is, how far could gravitational attraction deviate from an exact inverse square law without ...
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1answer
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Jupiter & Saturn
In his prog. on Jupiter, Brian Cox stated that the complex gravitational interplay, between Jupiter & Saturn, prevented Jupiter from drifting through the Asteroid Belt, and approaching our part of ...
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An ice cube orbiting the Earth
Recently I am stuck with a question about an ice cube that is orbiting the earth from a certain radius and it starts to melt down by the sun.
Which of the followings are wrong?
The cube will start ...
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What is the reason for Moon and satellite in free fall condition?
I am a high school student. I read in my book that moon and satellite are in free fall condition with Earth. I asked my teachers about this, but I'm not able to understand. Can anyone explain to me ...
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Conceptual question about wheels
I am trying to understand quite naively wheels in a specific framework.
Intro
We normally think of squares and circles as different concepts of shapes, but I am reframing it that both are polygons ...
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Why is the distribution of dark matter in a Galaxy different from the distribution of normal matter?
The dynamics of a galaxy are driven by gravity. And dark matter experiences the same gravitational forces as normal matter. The effects of other forces are very small in comparison. So why is the ...
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Do SR account for one sixth or one third of the anomalous perihelion shift?
In answers to two other questions on this site:
Mercury's Orbital Precession in Special Relativity
and
Do 2-body elliptic orbits precess in special relativity?
it is stated that special ...
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**Mathematical Derivation** of the fact that all planets will orbit on the same plane
There is some discussion about this Here. If an isolated system of particles under gravitational force is allowed to decrease its energy by means such as inelastic collision, then eventually all ...
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Numerical Solutions for Equatorial Orbits in the Kerr Black Hole
Currently, I am trying to find timelike orbits in the Kerr metric around the equator. The problem is that no matter which parameters I choose or the method I use I can't seem to get to physically ...
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Will extracting power from ocean tides affect the moon's orbit in the LONG run?
Conservation of energy says that any energy extracted from our ocean's tides would have to come from somewhere. Since these tides are a gravitational effect due to the moon, it would seem that the ...
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Do planets in elliptical orbits exhibit constant magnitudes of acceleration in their orbits?
I'm trying to reason through a problem. Consider Jupiter, which orbits the sun in an elliptical path. Is the magnitude of its acceleration constant throughout its orbit?
My reasoning leads me to ...
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Why are so few inclined circumbinary planets known?
For a research project I'm studying the orbits of circumbinary planets, most of these planets orbits are coplanar. However I was wondering if orbits with a high inclination could be stable. I made a ...
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How does the orbital radius affects the orbital velocity
I have a question says that "If the orbital radius of a satellite increase four times the orbital velocity will be ..." and the answer is that the velocity will be doubled !!
We studied that orbital ...
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1answer
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Prove acceleration in orbit with newtons second law
I want to prove that the acceleration in a orbit at a given point r=(x,y) is $a=-\frac{GM}{R^3}r$ (My professor said this can be proven by newtons second law, but he never explained in detail how). I ...
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Approximating the orbit of an object tied to another by a rope which is shortening
Working off my previous question, I think I've finally managed to describe what I'm wondering about in a quite clear, non-vague way.
Suppose we have an object $B$ tied to an object $A$ by a rope, ...
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Change of orbit with tangential impulse
I see a similar question: Change of orbit with a radial impulse. The answer to that question seems fine to me. In the answer, mention is made of this similar question, but it is not fully treated.
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Movement of an object tied to another
Suppose we have two objects $A$ and $B$, where $B$ is tied by a rope to $A$ with the slack pulled out, the initial tangential speed $c'(0)=(0,1)$ is perpendicular to $c(0)$ and $c(0) = (1,0)$, and ...
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Some questions concerning orbits of objects [closed]
I've been playing around with some physics problems and trying to figure out things by myself, mostly just for fun. I would appreciate if someone corrected my thoughts and gave me some feedback. I'm ...
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Velocity of an object orbiting on a string
First, I'm sorry if this question is dumb, incoherent or vague - I never really studied any physics and this might be out of my grasp, but I tried to apply some of the math I know and figure these ...
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1answer
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What is the energy source for Earth movements? [closed]
What is the source of energy responsible for Earth movements (rotation, translation, etc.)?
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Radial component of velocity at extreme distances
Suppose I am given that a planet's position with respect to some star is of the form $\textbf{r} = r\textbf{e}_{r}$. Then of course $\textbf{v} = \dot{r}\textbf{e}_{r} + r\dot{\theta}\textbf{e}_{\...
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If a body is moving under central force in a circle then how its path will be changed if it is subjected to a impulse [closed]
A particle of mass m moves under an attractive central force of $Kr^4$ with an angular momentum L
Find the frequency of the radial oscillations if the particle is given a small radial impulse and ...
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Trajectory of a satellite whose velocity is less than circular orbital velocity? [closed]
If the velocity of the satellite orbiting around a planet is reduced somehow...then what would it's trajectory looks like spiral(1) or elliptical(2) Or Does it depends on the velocity it has(less ...
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The Earth revolves around the Sun or the Sun revolves around the Earth
Well, in today's world we know that the earth resolves around the sun. But that is seen from frame of reference of sun or an observer stationary wrt sun.
From frame of reference of the earth, sun ...
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Help with Gravity Assist [closed]
In our scenario, a spaceship of mass 70,000 kg and velocity $v_o$ is planning on slingshotting around Earth and we're supposed to find what the exit velocity will be. The Earth is the origin in our ...
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1answer
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Does the density of an object play a role for it's gravitational effects?
My thought experiment:
We repalce our sun with an object of identical mass, rotation, shape, etc. but not the same density, i.e. the object would have a radius of 100km. The "replacement-time" would ...
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Why aren't satellites disintegrated even though they orbit earth within earth's Roche Limits?
I was wondering about the Roche limit and its effects on satellites.
Why aren't artificial satellites ripped apart by gravitational tidal forces of the earth?
I think it's due to the satellites being ...
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What are the forces behind the orbit of the Earth around the Sun?
Does the gravity of the sun alone affect the orbit of the earth around the sun?
Look at the image below,(Image is not to scale),
Is it that when earth is going from position 1 to position 2, it ...
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1answer
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Can satellites stay in orbit when the Earth is being accelerated?
In a TV show I'm watching, the people of Earth have decided to leave the solar system, and take Earth with them, so they've built a large number of powerful rocket engines on one side of the Earth (as ...
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2answers
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Why is the orbit of the Earth around the Sun very intricate?
The movement of the earth around the sun is very Goldilocky. Did it happen over the years as the orbit of earth averaged out into how it is now? Is there any chance of it (orbit) changing by itself in ...
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Revolution of Earth around the Sun
We study the orbit of many planets around the sun modelling it as a uniform circular motion.
Is this due to the fact that empirically we measured that the magnitude of the earth's velocity (for ...
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1answer
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Is there a general relativistic mass in general relativity?
In general relativity the energy of a test-body moving in a spherically symmetric gravitational field can be written as:
$$E=mc^2\left(\frac{\sqrt{1-\frac{2GM}{rc^2}}}{\sqrt{1-\frac{v^2}{c^2\left((1-\...
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Why does the Earth follow an elliptical trajectory rather than a parabolic one?
I was taught that when the acceleration experienced by a body is constant, that body follows a parabolic curve. This seems logical because constant acceleration means velocity that is linear and ...
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4answers
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Is the angular momentum in uniform circular motion zero?
In uniform circular motion the direction of linear velocity changes (although magnitude is constant), so linear velocity is not constant and we know that the formula of angular momentum contains ...
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3answers
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Kinds of orbits in two-body problem
I have a numerical simulation for two bodies moving under gravitational interaction, and some of the outputs are not cohering with my understanding of the theory.
My understanding of the theory:
In ...
