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The Winter 2010 issue of The Earth Scientist includes a variety of educational resources, ranging from astronomy to glaciers. Check out the other publications and classroom materials in our online store.
This is a composite image of the small moons of Saturn.
Click on image for full size
NASA

Janus

Janus was discovered by A. Dollfus in 1966. Janus is the 5th closest moon to Saturn, with a standoff distance of 151,472 km. Janus is one of the small moons, and is about the size of a county, at 110 x 80 km (75 x 53 miles) wide.

Janus and Epimetheus orbit Saturn together. They are only 50 km (33 miles) apart as they orbit Saturn, which is a little like having two moons in the same city. The fact that they are so close may mean that they are two pieces of what may once have been a single moon.

As a small moon, the composition and surface features of Janus are unknown.

Last modified January 19, 2001 by Jennifer Bergman.

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