proximity to Earth
The Moon has a more significant effect on ocean tides than the Sun because of its proximity to the Earth and relative size. Moon's gravitational force on the Earth is stronger than the gravitational force of the Sun, though the Sun is much larger and more massive because the Moon is nearer to the Earth than the Sun. The Moon's gravitational pull causes the oceans to bulge outward on the side of the Earth facing the Moon, creating a high tide.