24k views

### What can the KSP game actually teach about spaceflight and orbital mechanics, and what are its limitations?

I have seen at least several different users mention that they've found Kerbal Space Program helpful to understand issues of spaceflight and orbital mechanics. According to Wikipedia: While the game ...
• 149k
3k views

### How to calculate the planets and moons beyond Newtons's gravitational force?

The question Calculating the planets and moons based on Newtons's gravitational force was pretty much answered with two items: Use a reasonable ODE solver; at least RK4 (the classic Runge-Kutta ...
• 149k
2k views

### How to determine an algorithm for Low Earth Orbit propagation, considering perturbation from the moon, sun, etc?

I'm trying to determine an algorithm for orbit propagation for a satellite on LEO, with high accuracy in a six month time ...
3k views

### Where to find the best values for standard gravitational parameters of solar system bodies?

Where can I find the best values to use for standard gravitational parameters of solar system bodies for numerical simulation experiments? Here are two sets I've put together. The first set is from ...
• 149k
755 views

### Why are Keplerian elements used in TLEs instead of Cartesian state vectors?

Propagating a state vector seems easier, you just account for the gravity, change the velocity and update the position. It also allows to easily apply perturbations, etc. Additionally, the ...
• 525
238 views

### Why does the eccentricity of Venus's (and other) orbits as reported by Horizons vary based on the frame origin and basis?

I did try to think this through before posting, but I am going to need some explanation. In my (perhaps naïve) view, an ellipse will have the same eccentricity no matter what frame it is in. In ...
• 43
220 views

### Flat-spin transition manoeuvre: why is the angular momentum not constant?

In an article by Rahn and Barba, in which a flat-spin transition manoeuvre is investigated, the following figure is presented: I'm trying to reproduce this figure by integrating the following coupled ...
• 435
280 views

### Two Body Kepler Propogation: Errors from using float / single precision

I am looking into leveraging GPU's for two body orbit propagation. I am doing basic Kepler propagation, and only dealing with circular and elliptical orbits. I took a first shot at using single ...
• 405
509 views

### Planets positions determination

I am writing a 3D solar system simulator that features planets, asteroids, comets and Trans-Neptunian objects. It also includes daily "Close Approach" bodies from the Jet Propulsion Laboratory ...
• 83