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

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6
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3answers
97 views

Elliptical orbit changing as a star's mass increases

I'm studying Kepler's Laws, specifically the orbit of the Earth around the Sun. I know that if the Earth was more massive, the orbit would not be significantly affected. If the Sun was more massive, I ...
0
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0answers
24 views

Is it possible to determine perigee distance from distance recordings from a spacecraft to Earth?

If you are on a spacecraft orbiting earth in an elliptical orbit and were able to take measurements of the distance between the spacecraft and earth as well as the time intervals between those ...
1
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1answer
52 views

Conversion of satellite coordinates from ITRF to J2000

I have coordinates of various satellites in two coordinate systems: Cartesian coordinates in the international terrestrial reference frame (ITRF) RA / DEC in J2000 epoch, as derived from plate ...
1
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1answer
55 views

Reconciling geosynchronous orbits and why the moon is moving away

First time on PSE, and forgive me if the question doesn't make sense. Everything I've read, and the explanations make perfect intuitive sense, for why the moon is moving away from the earth is ...
15
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4answers
2k views

What would happen if the Earth was in a polar orbit around the sun?

This is a question that has been bugging me for a while now, I was wondering about the effects on the Earth if it was in different orbital situations to what it is now, and one of those was what would ...
0
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2answers
61 views

Maths of elliptical orbits

I have a simulation of the solar system that currently gives me circular orbits. I'm not 100% sure where I've limited my simulation to this, but probably it starts when I use $$v=\frac{2 \pi r}{T}$$ ...
0
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1answer
61 views

Launching of artificial satellites [closed]

Whose theory is used today during launching of artificial satellites, Newton's or Einstein's or any other? Which theory is better in launching of artificial satellites and other orbiting bodies, ...
0
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1answer
40 views

Orbital motion and likelihood of bodies colliding

An asteroid is in a highly eccentric elliptical orbit around the sun. The period of the asteroid's orbit is $90$ days. Which of the following statements is true about the possibility between a ...
7
votes
3answers
533 views

Questions on the movie Gravity (2013)

To start off, I'm not a physicist but a programmer, and only had a few years of physics education in high school so I'm sorry if I'm asking a stupid question. I just finished watching the movie ...
1
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2answers
67 views

Calculating speed of satellite in vacuum?

Satellite speed is $35\ \mathrm{km/s}$ after burn for $500\ \mathrm{ sec}$ and after some days or months this speed is reduced automatically $34$, $33$, $32$ respectively. Questions: How the ...
0
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3answers
153 views

What would become of the earth's orbit if half of the sun's mass were suddenly to disappear? [closed]

I shall assume that the sun is at rest, so before the half mass disappear, the orbit of earth is an ellipse.
1
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2answers
140 views

Why Sun is not able to attract mercury closer?

As sun have a huge amount of attraction pull force , why its not able to pull tiny mercury? Is the whole solar system works in a push and pull network? Why bigger planets like earth, Saturn and ...
-3
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1answer
57 views
0
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1answer
35 views

Why only binary star system produce ripples in space-time (gravitational waves)?

I saw a statement being made in a video, but it didn't explain why. It originally said, "stars orbiting each other does not create gravitational waves, binary system of two massive stars or black hole ...
2
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3answers
123 views

Shape of an inverse cube orbit?

If I have a particle orbiting a central force $$F=-k/r^3$$ what is the shape of the orbit (the radius as a function of the angle)?
1
vote
1answer
55 views

Consider a particle of reduced mass $\mu$ orbiting in a central force with $U=kr^n$ where $kn>0$ [closed]

Consider a particle of reduced mass $\mu$ orbiting in a central force with $U=kr^n$ where $kn>0$. (a) Explain what the condition $kn>0$ tells us about the force. Sketch the effective ...
1
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1answer
40 views

Minimum energy required to remove the satellite from its orbit to infinity?

My book says that minimum energy required to remove the satellite from its orbit is equal to its total energy (K.E+P.E). But shouldn't it equal to only the potential energy difference of satellite in ...
1
vote
2answers
65 views

Does the International Space Station always travels in the same path?

From the 3d visualization http://www.satflare.com/track.asp?q=25544#TOP (the right image with the red line indication the path of the ISS) it looks like always the ISS takes the same path. Is it the ...
1
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0answers
65 views

Conservation of Angular Momentum…or not?

This is my first post on physics stack exchange, but I thought the question was more appropriate than on that of math.stack. I'm currently designing a crude model of the sun-earth orbit (which I have ...
2
votes
2answers
127 views

In the hydrogen atom, why is the electron orbital spherical rather than flat like a 2D orbit plane?

In a hydrogen atom an electron is orbiting around a proton, similarly to a moon around a planet. The orbit of a moon around a planet is flat (2D) whereas the orbit of an electron around a proton is ...
3
votes
1answer
41 views

What happens when the Kepler Space Telescope 'catches up' to Earth?

Kepler is in an earth-trailing orbit with a period of 372.5 days, so it lags behind the Earth about a week each year. Doesn't that mean that, in about 52 years, we'll meet it from the other direction? ...
2
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2answers
48 views

Have there been studies on shapes of orbits or where the orbits would tend to around objects other than spheres?

I have looked on the internet and maybe I am not using the right search terms but I can not find anything concerning this topic. I am looking because I would think if a massive pole structure were ...
1
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2answers
65 views

Changing orbit of a space shuttle

In the figure here, a space shuttle is initially in a circular orbit of radius r about Earth. At point P, the pilot briefly fires a forward-pointing thruster to decrease the shuttle’s kinetic energy K ...
2
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1answer
52 views

Veterans Day Memorial in the U.S

For the ones who know about it: How many more times will the Veterans Day Memorial stones' holes "align" perfectly? Some info from this site: At precisely 11:11 a.m. each Veterans Day (Nov. ...
0
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0answers
32 views

Lunar orbit homework question

So what I did was find the potential energy of the lander at the 50km orbit and the 300km orbit, then I took the difference between the 2 potential energies and I though that would be the work done ...
2
votes
1answer
54 views

Time spent in eclipse of an object

Well consider an orbit - I'm trying to calculate the exact time spent in the shadow of the body you orbit around. An explanation of "shadow" (sun is positioned to the far left): For a circular ...
0
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0answers
64 views

Graduate level orbital mechanics book

I recently finished an undergraduate course in classical mechanics and really enjoyed the subject, particularly the sections regarding the mechanics of orbits. I am considering pursuing a graduate ...
3
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3answers
114 views

What is the distance between two objects in space as a function of time, considering only the force of gravity? [duplicate]

What is the distance between two objects in space as a function of time, considering only the force of gravity? To be specific, there are no other objects to be considered and the objects in question ...
0
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1answer
52 views

Why does Goldstein's derivation of orbits from Newton's law not yield the orbit consisting of symmetric oscillation along a line thru center of Sun?

Why does Goldstein's derivation of Keplerian orbits from Newton's law of gravity not yield the orbit consisting of symmetric oscillation along a line passing thru the center of the Sun? The fact that ...
2
votes
2answers
87 views

Center of mass chaotic in n-body gravitational interactions?

I wrote a gravitational particle simulation. To prevent the particles flinging off out of the screen, I added a bit of friction (it also makes the animation prettier as particles spiral into one ...
0
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0answers
43 views

Finding position with respect to time along a trajectory across a sphere (orbital mechanics)

When trying to find an object's position with respect to time on a ballistic trajectory along a curved surface, what equation should I use? I know that when adding force to an object to achieve ...
0
votes
5answers
63 views

Static model of the Earth motion

Believe it or not, an old man I know in 2015 still negates the Earth orbital motion around the Sun. He believes the earth is rotating on itself and acknowledges this gives day and night on every ...
0
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1answer
43 views

Deriving some uniform circular motion equations

My question basically boils down to this. How do we derive these relationships. 1.)What is the relationship between radius and centripetal force? (inverse, but why?) 2.)What is the relationship ...
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0answers
17 views

Can we use the planets and Sun to fling out a craft at relativistic speeds? [duplicate]

E.g. The Voyager crafts took various assists from the planets. Sun being much more massive, wouldn't a spacecraft gain much more energy from such a flyby on the correct trajectory? If so then what ...
2
votes
3answers
103 views

(How) can we determine mid-point on Earth's orbit?

The eccentricity of earth's orbit varies with time, but at present time its eccentricity is roughly mean e (0.0167). The position of equinoxes is far more complicated than I thought and it is not at ...
3
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0answers
99 views

From Newton to Kepler without infinitesimals

I've read some interesting calculus-free proofs of at least parts of the derivation of Kepler's Laws from Newton's gravitational force. One is of course Feyman's "Lost Lecture" (which was already ...
16
votes
3answers
2k views

Are there any exact data about Earth's orbit?

Wikipedia says that the Earth's orbit's axis is $a=149\ 598\ 000\ \mathrm{km}$ and its eccentricity is $e=0.016\ 7086$, but if we use these values to find distance at aphelion and perihelion we get ...
1
vote
1answer
78 views

How much fuel do I need to send cubesat 1kg from Earth orbit to Moon orbit? [closed]

How much fuel do I need to send cubesat 1kg from Earth orbit to Moon orbit? And how much stages? For i.e. C12H22O11 + KNO3, polyethylene + oxygen or kerosene + oxygen.
2
votes
1answer
30 views

Acceleration in an elliptical binary system

So I'm having a bit of a problem dealing with binary systems. I'm looking at acceleration in a stellar system and am not sure where to begin. Assuming both stars are of equal masses, they'd be ...
3
votes
0answers
34 views

Different time between equinoxes

I calculated from here that there are 16 104 096 seconds between the vernal and autumnal equinox, if I made no mistake, this is some 650 592 s longer than the other half orbit. I imagine this is due ...
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0answers
38 views

Earth to LEO, gravity drag and potential energy

A lot of references indicate takes about 9.4 km/s of delta-v to reach LEO. https://en.wikipedia.org/wiki/Low_Earth_orbit#Orbital_characteristics The delta-v needed to achieve low Earth orbit ...
2
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3answers
106 views

Explaning Motion of a Man and Spacecraft Orbiting the Earth [closed]

A man and spacecraft is orbiting around the earth. The man is outside the spacecraft and is not connected to the spacecraft in any way. The distance between the man and the spacecraft remain ...
3
votes
1answer
122 views

Orbital equations of motion with respect to energy

Consider the equations of motion of an object in an orbit around a central body. We use an inertial frame originating at centre of mass of the central body: $$ \frac{d\mathbf{r}}{dt} = \mathbf{V} ...
2
votes
1answer
53 views

Calculating mass of an orbiting body with force and acceleration

I'm new to physics, and it's a lot to take in- but there is a problem that I really can't seem to wrap my head around- finding the mass of an orbiting body, like an asteroid. I've looked around a lot ...
3
votes
1answer
103 views

Relation of orbital speed and eccentricity

Earth's eccentricity is 0. 0167 and speed at perihelion is 30.3 Km/s and at aphelion 29.3 with a difference of +/- 1. 0164 wrt average orbital speed Is this a coincidence or are the variations of ...
2
votes
0answers
67 views

Why do they think WT1190F is low density?

A piece of space debris WT1190F is in the news in part because it has been far from earth (farther than lunar distance) in the past but will re-enter earth's atmosphere in a few weeks. See this note ...
0
votes
1answer
69 views

Relation of orbital radius with linear velocity of satellite [closed]

If a planet is going around the sun in a circular orbit , and if suddenly (impulsively) it's orbital radius was increased , what would happen to the linear velocity of planet (With reason)
0
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0answers
35 views

Efficient orbit transfer

Well simple orbital (in plane) manoeuvres are quite easy and straight forward. Currently I found however an orbit I have a hard time calculating/reasoning the ideal path to get to. - Just as a note, ...
1
vote
1answer
50 views

What is the time of impact of a dropped item at a very high altitude [duplicate]

I'm trying to automate a landing at a specific spot in Kerbal Space Program and to do that I need to know when the estimated time of impact will be. In short, I'm trying to solve the following ...
0
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0answers
23 views

Time of an elliptical orbit

We know that T, the time of a revolution in an elliptical orbit is equal to the time of a circular orbit, can you tell what is the formula that relates time elapsed and space travelled (on the major ...