The Rings Around Saturn Must be Young

The argument goes like this, "The rings orbiting Saturn, Uranus, Jupiter, and Neptune are being rapidly bombarded by meteoroids. Saturn's rings, for example, should be pulverized and dispersed in about 10,000 years. Since this has not happened, planetary rings are probably quite young."

This argument is actually valid. The rings of Saturn are young! In fact, both Saturn and Jupiter have a large number of moons that revolve around the planets. The interaction of the orbits of these moons results in resonance between the moons that eventually leads to either the ejection of one of the moons from the orbit of the planet or (more likely) a near collision with the large planet. A near collision that takes the moon within the Roche limit results in the disintegration of the moon due to tidal forces, resulting in the formation of rings. The rings of Saturn are very young. The rings of Jupiter are much older, and nearly gone at this point. The (unstated) assumption that the rings must be the same age as the planets they revolve around is not valid.

Error: Invalid assumptions
Last updated March 31, 2008


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