Explore Alliance Presents: How Do You KNOW? – Episode #14: 'The Doomed Moons of Mars'

We all know that the gravitational field of any moon causes tides on its home planet. The height of the tide for a moon also depends upon the nature of the surface of the planet. If the surface is covered with water, such as an ocean or an inland sea, the tide can be many meters high as we see on the Earth.

Much work has been done to precisely measure the distance to Earth's moon, and we have found that it is slowly drifting away from our planet. But not all moons around planets are drifting away. Moons are fated to be cut loose from their home planet and drift away, or else to be shredded into relatively tiny particles and circle their planets as a spectacular ring. The two moons of Mars have different endings...

Dr. Barth helps us understand why all moons are eventually doomed on this episode of  'How Do You KNOW?'

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