Moon Trajectory

[vicesalles]

Hi, awesome job here! Do you know how moon trajectory can be calculated? I've reading about biodinamic gardening and they say that the trajectory of the moon (ascending or descending) is quite important for gardening...

Hrm, great question. This library isn't explicitly set up for calculating that, since its machinery is geared towards finding the moon's phase, not it's position. (In astronomical lingo, you want to know the derivative of the moon's altitude, and lune isn't set up to give us that!)

I have a separate project, https://github.com/darkskyapp/astro, which has the necessary moving parts to compute the moon's altitude, but doesn't expose it's derivative. (Though it shouldn't be difficult to add!)

@ryanseys, I suppose this is a scope question for you: should lune be expanded to compute all lunar phenomena? Or should the project be strictly limited to lunar phases? (In which case I'd probably move this ticket over to astro and make this possible there!)

[vicesalles]

Thank you @ironwallaby just stared astro. I'll check it later altough I have no clue about astronomy. Thank you for tellling me that I'm looking for the derivative of the moon's altitude, I didn't even know how to say it.

In astro, the use-case is complicated, unfortunately. If you open a ticket over there, I can get you an example that'll do what you want as soon as I get the chance!

[ryanseys]

I see no reason why this library could not expand to support other lunar phenomena, though I don't have the processing power & time myself to add any new features. I'm happy to review and merge any PRs you send over here, and @ironwallaby is also free to review and merge any features he'd like in this library too. Of course, please try to keep the API clean and simple and related to the moon 😛

(I also lack the bandwidth to make active contributions right now! Maybe in a few months :) )

Referencing darkskyapp/astro#3

[vicesalles]

Thank you @ryanseys

[mk-pmb]

I see no reason why this library could not expand to support other lunar phenomena

I wouldn't mind more features either. However, let's make sure the API is designed to allow spending CPU cycles only on the subset of phenomena that you actually care about (and maybe some closely related facts) in each query.

(I completely agree with that, FWIW, which is actually why I started contributing to this library in the first place. :) )