37 lines
1.6 KiB
HTML
37 lines
1.6 KiB
HTML
<html >
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<head >
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</head>
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<body >
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<mbp:pagebreak/>
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<tei-ms:entry>
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<tei-ms:orth><h1 align="center" >Saturn</h1></tei-ms:orth>
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</tei-ms:entry>
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<br />
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<div align="center" title="Saturn's great rings are impressive clouds of dirt."><img src="saturn.jpg" /></div>
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<p ><b class="first" >S</b>aturn's rings make it one of the most familiar, and
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spectacular images of astronomy, not to mention science fiction. When Galileo
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trained a primitive telescope on the planet for the first time in 1610, he was
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misled. From the poorly resolved image in his viewfinder, he believed Saturn to
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be a triple-system, with a large body in the center and smaller ones on each
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side.</p>
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<p >The rings may be much younger than the planet itself, and great
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mathematicians have found them worthy of contemplation. Laplace and James Clerk
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Maxwell calculated that Saturn's rings must consist of many smaller objects.</p>
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<p >Although the planet is almost the size of <a href="jupiter.htm">Jupiter</a>, its mass is but one third
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as great, giving Saturn the lowest mean density of any solar system object.</p>
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<p >As a gas giant, the planet has no single rotation period but rather a variety
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depending on latitude. Upper atmosphere clouds travel around the equator in as
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little as 10 hours and 10 minutes; clouds in high latitudes may take half and
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hour longer to pass across the planet.</p>
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<p >Based on gravitational field data, Saturn appears to have a solid core with a
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mass equivalent to up to 20 <a href="earth.htm">Earths</a>. As the most oblate planet, the pull of
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gravity at its equator is less than three quarters of that at the poles.</p>
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</body>
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</html>
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