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Is the rotation & the revolution of the earth slowing down?why?
A number of forces cause the slowing of the Earth’s rotation, but the strongest is tidal friction, a result of the moon’s gravity. The side of Earth closest to the moon feels its pull the strongest, the center of Earth—the point from which gravity is measured—is essentially neutral, and the side farthest from the moon feels its gravity less. That difference in gravitational pull stretches the Earth, which causes tides and tidal bulges.

Because they have mass—and thus, gravity—these bulges pull the moon forward or farther away from Earth by roughly four centimeters per year. But just as these bulges exert force on the moon, the moon exerts the opposite force on them, pulling them back toward it, creating friction and slowing down the planet’s rotation.

Using eclipse data from as far back as 2000 BC, scientists estimate that the Earth's rotation is slowing at approximately 1.7 milliseconds per solar day per century. In other words, the Earth day has grown by roughly 0.07 seconds in the last 4,000 years.


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