Nevertheless, the sun produces tides, too. At New and Full moons, the distortion effects of the moon and the sun work together to produce exceptionally large variations between low and high water. At first and last quarter moons, the distortion effects of the moon and the sun work against each other to produce exceptionally small distortion of the oceans, and abnormally small variations between low and high water. These times are called Neap Tides . Amount to rises and falls of about 20 cm.
Rotation of earth pulls tidal bulge ahead of moon.
Moon tries to slide it back. Friction of water against solid earth pulling back retards the spin of the earth, slows revolution of moon, and causes moon to recede from the earth. Evidence from fossil corals and rock strata that the day was 22H long 400 million years ago. Can be measured by laser radar. The day becomes the same as the month.