Astrophysicists reveal a multi-million-year pause in the extension of the Earth's day. Astrophysicists at the University of Toronto have solved a mystery: why Earth's day lengthens gradually under the influence of lunar tides, while the Earth's day lengthening pauses for more than a billion years. Their research shows that from about 2 billion years ago to 600 million years ago, sun-driven atmospheric tides counteracted the moon's influence, maintaining Earth's rotati...