text: why the high tide happens every day later 52 minutes than the day before?   suppose the sun, the earth and the moon are in a line and it full moon.   the moon takes 27.5 days to make an orbit around the earth. but as the earth has moved further in its orbit around the sun the moon needs two days more to arrive at the same position with the sun for a new full moon.  the difference amounts to 7.3%, which is 104 minutes per day. as in most places high tide happens twice a day, a high tide happens every day 104/2=52 minutes later than the day before.