Support for Satellites

[ophilli]

Hey @Canleskis! ephemeris-explorer is very cool.

I'm interested in rendering / displaying satellites. This can be easily done for their "current" orbits by taking their TLEs from sources like https://celestrak.org/ and then propagating using SGP. Would you be open to accepting some simple contributions to ephemeris-explorer in this direction?

This may be a bit antithetical to your current goals because it seems like you're interested in modeling orbits over decades but I think satellite propagations are probably only good for a week or so into the future.

Thanks, Owen

[Canleskis]

Hey, I'm definitely interested in supporting different models to describe orbits and I'm also very happy to receive contributions! The TrajectoryData trait and Trajectory struct and how they are used should have what is needed for all kinds of implementations and movement/plotting should work too.

I am still familiarising with TLEs however, so maybe the current state of things might make it difficult to implement, especially because they use Earth-centered inertial frames. The struct holding TLE data might have to store a clone of Earth's Trajectory in order to convert back (thankfully trajectory data is wrapped inside an Arc).