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0 votes
1 answer
62 views

Has our knowledge of astrophysics and gravity reached the point where we can accurately calculate Lagrange points?

is it possible for us today given the knowledge we possess of gravity and our success with inserting satellites in to steady/ geosynchronous orbit and any knowledge we have on the relative size (and ...
Matt Bartlett's user avatar
0 votes
0 answers
31 views

Restricted 3-body: one large mass and two smaller ones

A restricted 3-body problem is usually understood as two large bodies and one much smaller one that doesn't affect the motion of the other two. I am curious about a 3-body problem with one large body, ...
6 votes
7 answers
1k views

What changes the velocity perpendicular to radius in an elliptical orbit?

I'm working currently on a problem that asks to justify that angular momentum and kinetic energy conserves for a planet in an elliptical orbit. Although I've been taught that angular momentum should ...
RChen's user avatar
  • 69
0 votes
1 answer
61 views

Find eccentricity of orbit given the velocity and the semi-major axis

Is it possible to calculate eccentricity of orbit knowing only the semi-major axis and the velocity of both celestial bodies? If not, what other additional information is required. Does the fact that ...
Sid N's user avatar
  • 38
0 votes
1 answer
44 views

The magnetic force between the earth and the sun

There is a magnetic field around the earth and a stronger one around the sun. I guess there should be a magnetic force between the sun and earth. Now, shouldn't we take the magnetic force into account ...
Future Math's user avatar
2 votes
0 answers
37 views

When are two object guaranteed to keep getting further and further away?

In a two-body problem, it is known (if I understand correctly) that if the specific orbital energy of the system is $\varepsilon \geq0$, then the objects must eventually escape each other. My question ...
Remeraze's user avatar
  • 125
0 votes
1 answer
48 views

Speed of satellite in elliptical orbit [closed]

A satellite $S$ orbits a planet of mass $M$ in an elliptical orbit. At perihelion, $S$ has a tangential velocity of $v_1$ and is distance $r_1$ from the planet. At aphelion, $S$ has a velocity of $v_2$...
asdf's user avatar
  • 3
0 votes
1 answer
81 views

How to find the length of a travel between planets using the Hohmann Transfer?

I am trying to figure out how long it would take to get from one planet to another. This is for a worldbuilding project of mine. I would put my question on the Worldbuilding Stack Exchange but I ...
Martamo's user avatar
  • 101
0 votes
2 answers
62 views

Average Speed in one half of an elliptical orbit

I was wondering whether the average speed along one half of an elliptical orbit (say in a star planet system) had a closed form exact solution using Kepler's laws. My approach was using the ...
Echelon96's user avatar
1 vote
0 answers
28 views

Kepler orbit from mass, period, and eccentricity [closed]

I want to calculate the Keplerian orbital elements in the central force case. Given the mass M of the "sun" in kg, the eccentricity $e$ of the orbit, and the period $T$ in seconds, I believe ...
spraff's user avatar
  • 5,148
2 votes
2 answers
124 views

Orbiting body around a star

Let us assume there's a body with mass $m$ and velocity $v$, at a distance $r$ from another body of mass $M$. The velocity vector is perpendicular to the radial vector. With these values, how do we ...
Star Gazer's user avatar
1 vote
1 answer
78 views

Two bodies orbiting around barycenter

There are two bodies with masses $m_1$ and $m_2$ orbiting around barycenter. Distances to both bodies from barycenter are $r_1$ and $r_2$ . First body has known velocity $v_1$ as on the picture : My ...
michal12457's user avatar
0 votes
0 answers
25 views

How does moving the pericenter affect the apocenter?

A perfectly circular orbit of a constant height (distance from the center of mass of the orbited planet) around a perfectly spherical planet with smooth surface and no gravitational anomalies will ...
Parzh from Ukraine's user avatar
1 vote
1 answer
54 views

Is there a way to use the distances of the two opposite apsides to determine the eccentricity of an orbit?

Is there a way to use the distances of the two opposite apsides to determine the eccentricity of an orbit? The ratio between the distances (i.e. perihelion & aphelion) seem like they'd have a ...
madscribbles's user avatar
4 votes
0 answers
161 views

Confusion about Post-Newtonian orbital motion (Damour-Deruelle)

In their famous paper in 1985 (link), Damour&Deruelle describe the orbital motion for a binary system taking into account first-order post-Newtonian corrections (1PN). The solution is given in ...
gravitone123's user avatar

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