Astronomy Stack Exchange is a question and answer site for astronomers and astrophysicists. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

How does one compute the right ascension and declination of the Moon at a given time (or for that matter, the altitude and azimuth)?

share|improve this question
Do you want to know the equations or just a calculator? – Py-ser Jun 13 '14 at 2:35
Equations (fill) – ruadath Jun 17 '14 at 19:02
I assume you don't want to use an online/email solution like is that correct? How much accuracy do you seek? You can replicate HORIZONS calculations if you really want to. I assume you're looking at the geocentric ra/dec/alt/az? The actual position of the moon varies up to 1 degree depending where on Earth you are. – barrycarter Oct 8 '14 at 20:31
Does this question not help?… – called2voyage Jun 24 '15 at 17:58
The computation of the position of the Moon is rather complex (depending on the desired accuracy) and requires a few pages of equations. These can be found in e.g. this paper: – AstroFloyd Jul 16 at 12:57

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.