The phases of the moon are caused by the relative positions of the moon, Earth, and sun. As the moon orbits around Earth, different amounts of sunlight are reflected off its surface, creating the different phases we see from Earth.
The phases of the moon occur once every 29.5 days, which is the length of the moon's synodic period. This means that it takes 29.5 days for the moon to return to the same phase, such as from full moon to full moon.
During a full moon, the moon and sun have an angular separation of 180 degrees. This means that they are on opposite sides of the sky, with the moon fully illuminated by the sun's light.
The angular separation between the moon and sun changes during different phases because of the moon's orbit around Earth. As the moon moves in its orbit, the angle between the sun, moon, and Earth changes, resulting in different amounts of sunlight being reflected off the moon's surface.
Yes, the angular separation between the moon and sun can affect tidal patterns on Earth. As the moon's phase changes, so does its gravitational pull on Earth's oceans, resulting in different tidal patterns. The sun also contributes to tides, but to a lesser extent.