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 at all in comparison to its width for, although the distance from one side to the other of the entire ring is about 172,000 miles, its edge is estimated as only about 62 miles.

When the rings are open, the dark shadow of Saturn's planet may be seen against the light of these rings.

This shadow proves that the dull, yellowish glow on the planet is reflected sunlight, and that the planet does not shine with its own light, as a star.

Besides all the tiny moonlets in the beautiful ring, ten large moons whirl about the planet Saturn. These give Saturn a system with a radius of 8 million miles, which is quite extensive compared to the earth and moon system which has a radius of 240,000 miles.

The moons of Saturn range in size from about 200 miles to nearly 300 miles in diameter but being so far away only Titan, the largest, can be seen except in a large telescope. These satellites were given the names of the brothers and sisters of the God of Time and are called Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Hyperion, Japetus, Phœbe and Themis.

Titan, the largest satellite, is 771,000 miles distant from the planet. The nearest one is only 117,000 miles away but there are also three others which are closer to the planet than our moon is to us. Phœbe, the most distant one, is almost 8,000,000 miles away and takes nearly 18 months to make a revolution. It appears as a full moon only once in a year and a half—quite a contrast to Mars' little Phobos who goes through his phases one and a half