People who live at the ocean coast know that the tides are the highest during full moon and new moon. Why is it so?
High tides are caused by the terrestrial and solar attraction of the waters of the great oceans. One tidal “hump” forms in the direction towards Moon, another – from the opposite side of Earth. The height of Moon tides is approximately twice as high as that of the solar ones. During the new moon phase the directions towards Moon and Sun are the same, during the full moon they are opposite. In both cases the “humps” of Moon and solar tides are algebraically added.