During which two phases of the Moon do neap tides take place?
Neap tides occur during the first and third quarter phases of the Moon. To understand why, let me explain the concept of neap tides and their relationship with the phases of the Moon.
Tides are caused primarily by the gravitational pull of the Moon and, to a lesser extent, the Sun. The gravitational force exerted by the Moon attracts water on Earth, causing a bulge of water on the side of the Earth that is facing the Moon. However, the gravitational force also creates a second bulge on the opposite side of the Earth, called the antipodal bulge.
During the new moon and full moon phases, the Sun, Moon, and Earth align in a straight line, creating a stronger gravitational force and resulting in higher high tides, known as spring tides. These spring tides occur twice a month.
On the other hand, during the first and third quarter moon phases, the Sun, Earth, and Moon form a right angle, which means their gravitational forces partially counteract each other. The gravitational pull of the Sun partially cancels out the gravitational pull of the Moon, resulting in lower high tides, known as neap tides. Neap tides also occur twice a month, roughly a week after each spring tide.
So, to summarize, neap tides occur during the first and third quarter moon phases when the gravitational forces of the Sun and Moon partially offset each other, resulting in lower high tides.