Isaac Newton, renowned for his immense contributions to physics and mathematics, significantly advanced our understanding of tides. Through his work in the late 17th century, Newton debunked previous theories linking tides to spiritual forces or the Earth’s motion, instead correctly attributing them to gravitational forces.
In his theory, Newton proposed that the gravitational pull from the Moon and, to a lesser extent, the Sun, generates the oceanic tides we observe. These gravitational forces cause the oceans to bulge out towards and away from the Moon, leading to the regular rise and fall of sea levels known as tides. According to Newton’s calculations, the Moon’s influence results in a deep-water tide rise of about 20 inches (50 centimeters), while the Sun contributes about half of that effect.
Further, Newton’s insights extended to the understanding that tidal forces also affect the solid Earth, causing it to bulge slightly under the same gravitational influences. This deformation, both in Earth’s solid crust and in its oceans, leads to a phenomenon known as tidal friction. This friction has long-term effects on Earth’s rotation and the Moon’s orbit, gradually slowing down Earth’s spin and causing the Moon to recede from Earth at a rate of approximately 13 feet (4 meters) per century.
Newton’s work laid the foundation for modern oceanography and significantly contributed to our understanding of the Earth-Moon system. His theories on tides remain a cornerstone in the field of gravitational studies and continue to influence scientific exploration and understanding of celestial mechanics.
