# Simulate earth, moon, sun constellation with dates

I would like to simulate the three object distance, specifically the distance of the moon to both, sun and earth for further investigation into tide prediction.

What would be a good starting point to browse? Do any (preferably python) libraries exist for this? My use is to query the function with a date and it would spit out the distance.

A first model I would be happy to start with would be basic circular trajectories and expand to elliptical & inclinations from there.

• astronomy.stackexchange.com/questions/13488 might be a good start – barrycarter Oct 7 '19 at 23:50
• Hi @ElDude for Python solutions my personal recommendation is to use Skyfield as a quick, self-contained solution. It downloads an ephemeris and interpolates it for you in a very pythonic way, so with just a few lines you can get everything you want, including "query wtih a date and spit out the distance" using .separation_from(). – uhoh Oct 8 '19 at 4:39
• Check issue #228 for updates on constellations. See barrycarter's comment above for a wide range of options. Consider closing as dupicate(?) or perhaps refine your question to something specific that's not answered there? – uhoh Oct 8 '19 at 4:40