Reputation: 41
In reading TLE and calculating the orbit of satellites, does PyEphem regard the earth as the sphere or as the ellipse ?
Upvotes: 2
Views: 777
Reputation: 89415
The underlying astronomy library beneath PyEphem is named libastro, and here is its code for doing satellite computations:
https://github.com/brandon-rhodes/pyephem/blob/master/libastro-3.7.5/earthsat.c
It looks like it simply considers the Earth a sphere; the only place that I see the shape of the Earth even coming into the calculation is where the height is produced from its distance from the Earth's surface, where it just uses a constant radius instead of anything fancier:
#if SSPELLIPSE
#else
*Height = r - EarthRadius;
#endif
So I think your answer is “sphere.”
Upvotes: 2