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### Calculating orbital properties after an instantaneous burn not at apogee/perigee

Logically the problem of a satellite in orbit around the Earth can be fully defined by the position and velocity of the satellite (assuming a perfectly spherical Earth etc.). However when I try and ...
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### How to find orbital elements of a binary system

I'm trying to find the rate of precession of a binary system consists of two similar mass stars A and B, so I need to find the value of the argument of periapsis $\omega$ first, with velocity and ...
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### How to calculate new periapsis and apoapsis after orbital velocity change

I'm working on a way of simulating orbits for a video game I'm making. It works by taking the apoapsis, periapsis and current distance and calculating from there the velocity, radial velocity, period ...
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### Converting Cartesian vectors to Keplerian Orbital elements - having problems

I have my position and velocity vectors, and also the mass and position of the sun. I need to convert my vectors to the Keplerian Orbit elements, but I can't get a definite number when I do. The orbit ...
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### Keplerian Orbital Elements ↔ Cartesian ECEI with WGS84 Corrections

I'm trying to write code to go back and forth between equatorial KOE (Keplerian Orbital Elements) and ECEI (Cartesian). ECEI→KOE I found here: How to programmatically calculate orbital elements ...
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### Help with Cartesian State Vectors → Keplerian Orbit Elements C#

EDIT I am currently attempting to try the standard Cartesian State Vectors to Keplerian Orbit Elements conversion but i am having problems getting my head around the formulas and the use of vectors. ...
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### Orbit, circularizing, apogee/perigee

First - my question: After the orbit insertion, in the coast stage, and assuming perigee is out of the atmosphere, and neglecting any external forces and influences - is the orbit now "fixed"? As in, ...
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### How would off-apsis burn affect the angle and position of new apoapsis

Let's say you have an elliptical orbit, if you burn prograde at the periapsis, you extend the apoapsis by some factor(according to vis-viva equation). But if you burn prograde on somewhere during the ...
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### Why is the eccentricity vector used to describe near-circular orbits?

When dealing with near-circular orbits I've seen the usage of the eccentricity vector defined as $$(e_x,e_y) = (e\cos\omega, e\sin\omega)$$ I've seen this in Schaubs' "Analytical mechanics of ...
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### Calculating and Drawing the orbit of a body in a 2D gravity simulation in python

I'm making a space exploration game and its in a 2d plane so no z axis, and I'm using Newton's law of universal gravity, I would really like to calculate anddraw the predicted trajectory of a body, ...
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### Can I convert from TEME to Keplerian orbital parameters?

I'm a MSC student in computer science. For my thesis I'm using SGP4 tool to propagate a LEO satellite. If I have understood rightly, the SPG4 returns the two state vectors r and v in TEME format. (...
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### Calculating dV to raise apoapsis at an arbitrary point of an orbit

This is similar to another StackExchange post (right down to the Kerbal Space Program mentions), but with a different approach. The question I'm trying to solve is thus: Given current orbital state ...
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### Satellite Ground Track From ECEF Frame Position And Velocity Vector

The above question may sound naive. I am trying to understand how satellite ground track can be computed when satellite position and velocity vectors are available from on-board GPS receiver of a low ...
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### What are the symbol definitions in the equations for finding orbital elements?

I've been looking at the answer to this question on how to convert position and velocity to orbital elements, but some of the symbols are not defined and there are no reference links for those symbols....