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cosinekitty / astronomy

Astronomy Engine: multi-language calculation of Sun, Moon, and planet positions. Predicts lunar phases, eclipses, transits, oppositions, conjunctions, equinoxes, solstices, rise/set times, and other events. Provides vector and angular coordinate transforms among equatorial, ecliptic, horizontal, and galactic orientations.
MIT License
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Demo: search for when Moon is most north/south + crossing equator #275

Open cosinekitty opened 1 year ago

cosinekitty commented 1 year ago

It would be fun to have a demo that shows how to search for when the Moon is most north or south of the celestial equator (max/min declination), and when it crosses through the equatorial plane (declination = 0).

hidp123 commented 1 year ago

Hi, something related to this: is it possible to get the moon's orbit inclination angle via astronomy-engine?

cosinekitty commented 1 year ago

The angle between the Moon's instantaneous orbital plane around the Earth, with respect to the Earth's orbital plane around the Sun, is 5.145° as described here. However, the intersection of these planes (the nodes) keeps changing in something called the Saros cycle.

I'm not sure if this is what you are talking about. Can you describe in more detail what you are trying to do? It helps to know what the goal is to answer a question like this.

hidp123 commented 1 year ago

I'm not sure of the exact term, but it's the one that is related to the moon's declination. Unless it is the max dec for that orbit?

cosinekitty commented 1 year ago

I still don't have a clear picture of what problem you are trying to solve, so it's not clear how to help you. Can you explain what your goal is?

cosinekitty commented 1 year ago

cea015855881c95369c30d3aa29c8cd1eb2bfaa2 adds moon_north_south.js demo that calculates extreme equatorial declinations and ecliptic latitudes. It does not find equatorial nodes, but this could be added later.