Sinusoidal moon phases?

May 2021 3 218 Report

Sinusoidal moon phases?

Is there a specific sinusoidal equation for the phases of the moon, no tides or waves. This is for a Math analysis project so the most specific answer (or a website with a specific answer) for the equation would be highly appreciated :)

Science & Mathematics / Astronomy & Space

bikenbeer2000

Verified answer

The average time between successive same phases of the Moon is 29.5306 days. But the Moon moves in an elliptical orbit so this interval is not constant.

One method is to assume that the Moon (and Earth) move in a circular orbits and calculate the time of each phase on this basis. These would then occur at equal time intervals. Let's call these the mean phases. Then a number of sinusoidal corrections of the type Asin(B + Ct) are added where A is the amplitude of the time correction, B is an angle at a certain epoch (start time), C is the rate of change of the angle and t is the time since the epoch. B is a function of the positions of the Moon and/or Earth in their orbits.

Add these corrections to the mean phase time to obtain the true phase time.

The method is given in Chapter 47 of Astronomical Algorithms by Jean Meeus.

2 votes Thanks 2

engle

Haha Carissa i'm additionally attempting to discover stuff for Pointer's class! :P i've got not began yet . lol. i'm questioning of doing while toddlers are born. she talked approximately that did not she? :)

0 votes Thanks 0