tidal force

Definition

Astronomy

  • force exerted on one astronomical body by another and tending to alter its shape. Tides were first identified in the Earth-Moon system by observations of obvious changes in sea level, but have since been observed in the Earth’s atmosphere and solid body, as well as in the Moon. They are also an important part of the interactions between closely orbiting stars, colliding galaxies and other astronomical bodies on all scales.
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