Saturn+-+SM

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 * ||  || [[image:http://www.esa.int/global_imgs/print_it.gif width="34" height="13" caption="printer friendly page" link="http://www.esa.int/esaMI/Cassini-Huygens/SEMPQ6HHZTD_2.html"]] ||
 * Saturn's atmosphere**


 * [[image:http://1-ps.googleusercontent.com/h/www.universetoday.com/wp-content/uploads/2008/05/580x285xcassinirings-580x285.jpg.pagespeed.ic.j5eGTa60zD.jpg width="199" height="284" caption="Cassini's image of Saturn and Earth." link="http://www.universetoday.com/wp-content/uploads/2008/05/cassinirings.jpg"]] || [[image:http://i.space.com/images/i/13431/i02/saturn-giant-storm-head.jpg width="176" height="177" caption="Monster storm head on saturn."]] ||  || [[image:http://ep.yimg.com/ca/I/spaceimages_2198_29111469 width="176" height="166" align="left" caption="Saturn is the 6th planet from the sun." link="http://ep.yimg.com/ca/I/spaceimages_2193_29551732"]] || [[image:http://t3.gstatic.com/images?q=tbn:ANd9GcQDGw_NiRHiNPSq3J5cgIdzub8ve8Pb8QbG9fLdnq1AfqxWFksJdt6_m8QAIA width="300" height="168"]] ||   ||   || [[image:http://saturn.jpl.nasa.gov/assets/science/moons/images/main_flash_image.jpg width="426" height="263" caption="Saturn's Moons"]] ||
 * Name || Discovery Date || Discoverer || Distance from Saturn (103 km) || Mass (1020 kg) || Radius (km) || Orbital Period (days) ||  ||
 * Mimas (SI) || 1789 || W. Herschel || 185.52 || 0.375 || 209 x 196 x 191 || 0.9424218 ||
 * Enceladus (SII) || 1789 || W. Herschel || 238.02 || 0.65 || 256 x 247 x 245 || 1.370218 ||
 * Tethys (SIII) || 1684 || G. Cassini || 294.66 || 6.27 || 536 x 528 x 526 || 1.887802 ||
 * Dione (SIV) || 1684 || G. Cassini || 377.40 || 11.0 || 560 || 2.736915 ||
 * Rhea (SV) || 1672 || G. Cassini || 527.04 || 23.1 || 764 || 4.517500 ||
 * Titan (SVI) || 1655 || C. Huygens || 1221.83 || 1345.5 || 2575 || 15.945421 ||
 * Hyperion (SVII) || 1848 || W. Bond || 1481.1 || 0.2 || 185 x 140 x 113 || 21.276609 ||
 * Iapetus (SVIII) || 1671 || G. Cassini || 3561.3 || 15.9 || 718 || 79.330183 ||
 * Pan (SXVIII, S/1981 S13) || 1990 || M. Showalter || 133.583 || 0.00003 || 10 || 0.5750 ||
 * Atlas (SXV, S/1980 S28) || 1980 || R. Terrile || 137.670 || 0.0001 || 18.5 x 17.2 x 13.5 || 0.6019 ||
 * Prometheus (SXVI, S/1980 S27) || 1980 || S. Collins || 139.353 || 0.0033 || 74 x 50 x 34 || 0.6130 ||
 * Pandora (SXVII, S/1980 S26) || 1980 || S. Collins || 141.700 || 0.0020 || 55 x 44 x 31 || 0.6285 ||
 * Epimetheus (SXI, S/1980 S3) || 1966 || R. Walker || 151.422 || 0.0054 || 69 x 55 x 55 || 0.6942 ||
 * Janus (SX, S/1980 S1) || 1966 || A. Dollfus || 151.472 || 0.0192 || 97 x 95 x 77 || 0.6945 ||
 * Methone (SXXXII, S/2004 S1) || 2004 ||  || 194 ||   || 3 || 1.01 ||
 * Pallene (SXXXIII, S/2004 S2) || 2004 ||  || 211 ||   || 4 || 1.14 ||
 * Calypso (SXIV, S/1980 S25) || 1980 || B. Smith || 294.66 || 0.00004 || 15 x 8 x 8 || 1.8878 ||
 * Telesto (SXIII, S/1980 S13) || 1980 || B. Smith || 294.66 || 0.00007 || 15 x 12.5 x 7.5 || 1.8878 ||
 * Helene (SXII, S/1980 S6) || 1980 || Laques and Lecacheux || 377.40 || 0.0003 || 18 x 16 x 15 || 2.7369 ||
 * Polydeuces (SXXXIV, S/2004 S5) || 2004 ||  || 377.40 ||   || 4 || 2.74 ||
 * Kiviuq (SXXIV, S/2000 S5) || 2000 || International Team of 8 Astronomers || 11,370 ||  || 7 || 449 ||
 * Ijiraq (SXXII, S/2000 S6) || 2000 || International Team of 8 Astronomers || 11,440 ||  || 5 || 451 ||
 * Phoebe (SIX) || 1898 || W. Pickering || 12,952 || 0.072 || 115 x 110 x 105 || 550.48* ||
 * Paaliaq (SXXI, S/2000 S2) || 2000 || International Team of 8 Astronomers || 15,200 ||  || 10 || 687 ||
 * Skathi (SXXVII, S/2000 S8) || 2000 || International Team of 8 Astronomers || 15,650 ||  || 3 || 729* ||
 * Albiorix (SXXVI, S/2000 S11) || 2000 || Gladman, et. al || 16,390 ||  || 13 || 738 ||
 * Erriapo (SXXVIII, S/2000 S10) || 2000 || International Team of 8 Astronomers || 17,610 ||  || 4 || 871 ||
 * Siarnaq (SXXIX, S/2000 S3) || 2000 || International Team of 8 Astronomers || 18,160 ||  || 16 || 893 ||
 * Tarvos (SXXI, S/2000 S4) || 2000 || International Team of 8 Astronomers || 18,240 ||  || 7 || 926 ||
 * Mundilfari (SXXV, S/2000 S9) || 2000 || International Team of 8 Astronomers || 18,710 ||  || 3 || 951* ||
 * Narvi (SXXXI, S/2003 S1) || 2003 ||  || 18,720 ||   || 3 || 956* ||
 * Suttungr (SXXIII, S/2000 S12) || 2000 || Gladman, et. al || 19,470 ||  || 3 || 1017* ||
 * Thrymr (SXXX, S/2000 S7) || 2000 || International Team of 8 Astronomers || 20,470 ||  || 3 || 1089* ||
 * Ymir (SXIX, S/2000 S1) || 2000 || International Team of 8 Astronomers || 23,100 ||  || 8 || 1312* ||
 * S/2004 S07 || 2004 ||  || 19,800 ||   || 3 || 1103* ||
 * S/2004 S08 || 2004 ||  || 22,200 ||   || 3 || 1355* ||
 * S/2004 S09 || 2004 ||  || 19,800 ||   || 3 || 1077* ||
 * S/2004 S10 || 2004 ||  || 19,350 ||   || 3 || 1026* ||
 * S/2004 S11 || 2004 ||  || 16,950 ||   || 3 || 822 ||
 * S/2004 S12 || 2004 ||  || 19,650 ||   || 3 || 1048* ||
 * S/2004 S13 || 2004 ||  || 18,450 ||   || 3 || 906* ||
 * S/2004 S14 || 2004 ||  || 19,950 ||   || 3 || 1081* ||
 * S/2004 S15 || 2004 ||  || 18,750 ||   || 3 || 1008* ||
 * S/2004 S16 || 2004 ||  || 22,200 ||   || 2 || 1271* ||
 * S/2004 S17 || 2004 ||  || 18,600 ||   || 2 || 986* ||
 * S/2004 S18 || 2004 ||  || 19,650 ||   || 3 || 1052* ||
 * S/2005 S01 || 2005 ||  || 136.5 ||   || 3 || 0.59 ||   || [[image:http://saturn.jpl.nasa.gov/images/blank-space.gif width="100" height="1"]] ||   || [[image:http://saturn.jpl.nasa.gov/images/blank-space.gif width="10" height="1"]] ||
 * [[image:http://saturn.jpl.nasa.gov/images/blank-space.gif width="1" height="10"]] ||  ||



**Works Cited** **Sources** : Include the source information for all of the magazine articles, reference sources (encyclopedias) and web site pages that were used to complete your project. The source information for encyclopedias may be found at the end or beginning of each entry in iCONN. When using periodicals, the publication information will be at the beginning or end of the article. This needs to be formatted for MLA standards. If it is not labeled 'Source Citation' it can be formatted appropriately by using EasyBib.com. You should use EasyBib for the web sites. The final Works Cited should be listed in alphabetical order by the first word of the source citation.


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"Milky Way." //Kids InfoBits Presents: Astronomy//. Gale, 2008. Reproduced in Kids InfoBits. Detroit: Gale, 2012. "The Milky Way." //WMAP's Universe//. NASA, 28 June 2010. Web. 06 Mar. 2012. . Vergano, Dan. "Galaxy Bracketed by Big Bubbles." //USA Today// 10 Nov. 2010: 05A. Web. 6 Mar. 2012.

Saturn." //U*X*L Encyclopedia of Science//. U*X*L, 2008. //Gale Science In Context//. Web. 6 Mar. 2012. Document URL
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[|www.esa.int]

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U*X*L Encyclopedia of Science, May 1, 2008

Saturn

Saturn, the sixth planet from the Sun, is named for the Roman god ofagriculture, who was based on the Greek godCronus. The second largest planet in the solar system, it measures almost 75,000miles (120,000 kilometers) in diameter at its equator. Despite its large size, Saturn is the leastdense of all the planets. It is almost 30 percent less dense than water; placed in alarge-enough body of water, Saturn would float.

Saturn completes one rotation on its axis very quickly, roughly 10.5 Earth hours. As a result of this rate of spin, theplanet has become flattened at it poles. The measurement around its equator is 10 percent greaterthan the measurement around the planet from pole to pole. In contrast to the length of its day,Saturn has a very long year. Lying an average distance of 887 million miles (1.4 billion kilometers)from the Sun, Saturn takes 29.5 Earth years tocomplete one revolution.

Saturn consists primarily of gas. Its hazy yellow clouds are made ofcrystallized ammonia, swept into bands by fierce, easterlywinds that have been clocked at up to a speed of 1,100 miles (1,800 kilometers) per hour at itsequator. Winds near the poles, however, are much tamer. Covering Saturn's surface is asea of liquid hydrogen and helium that graduallybecomes a metallic form of hydrogen. This sea conducts strong electric currents that, in turn,generate the planet's powerful magnetic field. Saturn's core, which is several timesthe size of Earth, is made of rock and ice. Theplanet's atmosphere is composed of about 97 percent hydrogen, 3 percent helium, andtrace amounts of methane and ammonia. Scientists estimatethe surface temperature to be about -270�F(-168�C).

About every 30 years, following Saturn's summer, a massive storm takes place on the planet. Known asthe Great White Spot, it is visible for nearly a month, shining like a spotlight on theplanet's face. The spot then begins to break up and stretch around the planet as a thickwhite strip. The storm is thought to be a result of the warming of the atmosphere, which causesammonia to bubble up, solidify, and then bewhipped around by the planet's monstrous winds.

Saturn's most outstanding characteristic are its rings. The three otherlargest planets (Jupiter, Uranus, andNeptune) also have rings, butSaturn's are by far the most spectacular. For centuries, astronomers thought the ringswere moons. In 1658, Dutch astronomer Christiaan Huygens first identified the structures aroundSaturn as a single ring. In later years, equipped with stronger and stronger telescopes,astronomers increased the number of rings they believed surrounded the planet.

In 1980 and 1981, the Voyager 1 and Voyager 2 space probes sent back the first detailedphotos of Saturn and its spectacular rings. The probes revealed a system of over 1,000 ringletsencircling the planet at a distance of 50,000 miles (80,000 kilometers) from its surface.

The rings, which were estimated to be one mile (1.6 kilometers) thick, are divided into threemain parts: the bright A and B rings and the dimmer C ring. The A and B rings are divided by agapp called the Cassini Division named for it discoverer, seventeenth-century Frenchastronomer Giovanni Domenico Cassini. The A ring itself contains a gap, called the EnckeDivision after German astronomer Johann Encke, who discovered it in 1837. The Encke Divisioncontains no matter, but the Voyager missions found that the Cassini Division contains at least 100tiny ringlets, each composed of countless particles. Voyager confirmed the existence of puzzlingradial lines in the rings called "spokes," which were first reported by amateurastronomers. Their nature remains a mystery, but may have something to do with Saturn'smagnetic field. Saturn's outermost ring, the F ring, is a complex structure made up ofseveral smaller rings along which "knots" are visible. Scientists speculate that theknots may be clumps of ring material, or mini moons.

While scientists do not know the full composition of the rings, theydo know that the rings contain dust and a large quantity of water. The water isfrozen in various forms, such as snowflakes, snowballs, hailstones, and icebergs. The forms rangein size from about 3 inches (7.6 centimeters) to 30 feet (9 meters) in diameter. Scientists are alsonot sure how the rings were formed. One theory states that they were once larger moons thatwere smashed to tiny pieces by comets or meteorites. Another theory holds that the rings arepre-moon matter, cosmic fragments that neverquite formed a moon.

Saturn has at least 57 moons, of which about three dozen have received officially sanctioned names from theInternational Astronomical Union. All the known moons are composed of about30 to 40 percent rock and 60 to 70 percent ice. All but two have nearly circular orbits and travelaround Saturn in the same plane.

Christiaan Huygens discovered Saturn's first moon Titan, in 1655. Itis the only moon in the solar system with a substantial atmosphere,which is composed mainly of nitrogen. Voyager1 revealed that Titan may have seas of liquid methane bordered byorganic tarlike matter. Titan's thick blanket of orange clouds, however,prevent a direct view of the surface.

Our best source of information about Saturn in the early 2000s has been the Cassini-Huygens, spacecraft, launched by the National Aeronautics and Space Administration and the European Space Agency on October 15, 1997. The probe consists of two parts, an orbiter (Cassini) and a probe carried by the orbiter (Huygens). The Cassini-Huygens mission plans call for the orbiter to circle both Saturn and Titan and then to drop the probe through the atmosphere of Titan and onto its surface. Cassini-Huygensreached Saturn on July 1, 2004, and went into orbit around the planet. Mission plans call for 74 complete orbits around the planet, 44 flybys of Titan, eight "targeted" (focused specifically) flybys of six other Saturn moons, and 30 additional flybys of the planet's other satellites.

The Huygens probe was released from the Cassini orbiter on December 25, 2004. It then traveled through Titan's atmosphere for a period of 21 days, collecting data and relaying it back to Cassini which, in turn, sent the data on to Earth observation stations. Overall, Huygens collected 2 hours, 27 minutes, 13 seconds of data during its descent through the atmosphere and an additional 1 hour, 12 minutes, 9 seconds of data while resting on the satellite's surface. This quantity of data was much greater than space scientists had expected or hoped for.

One of Huygens's most interesting discoveries about Titan's atmosphere was the presence of methane clouds near the satellite's south pole. Scientists interpret those data to conclude that Titan may have weather patterns somewhat similar to those on Earth. The probe also made some exciting discoveries about the satellite's surface. It found a large, continent-size region named Xanadu that is unusually reflective of radar waves. After years of study with the Cassini probe, scientists concluded that Xanadu is probably a high plateau region covered in large part with water ice.

In 2006, Cassini radar imaging showed that Titan's north and south polar regions are dotted with seas of liquid ethane and methane, at least one larger than Lake Superior. This makes Titan the only body in the solar system, other than Earth, known to have open bodies of liquid on its surface.

In April 2008, the spacecraft's mission was extended until at least 2010.

By the early 2000s, evidence gathered by space probes had shown that several moons of planets in the outer solar system--Jupiter's Europa, Callisto, and Ganymede, Saturn's Enceladus, and possibly Neptune's Triton--contain large subsurface water oceans covered by frozen crusts of dirty ice. In early 2008, Titan was added to the list when scientists announced that evidence from the Cassini probe showed that the entire surface of Titan is afloat on a thick subsurface ocean that separates the crust from the moon's rocky core. Because the whole rigid surface of Titan is free to move on this underlying ocean, seasonal wind shifts cause it to rock back and forth more than they would if Titan were solid from surface to core. Measurement of this rocking--which also occurs on Earth, though to a much slighter degree--revealed the presence of the subsurface ocean.

Saturn is a large gas planet with an [|atmosphere] composed of hydrogen and helium. Saturn's rapid spin tends to flatten out the poles while causing a bulge at its equator. The winds in Saturn's atmosphere reach speeds up to 1800 [|kilometers] per hour! Astronomers see [|large white spots (or clouds) on Saturn] which they believe are storms. Just like Jupiter, Saturn emits twice as much heat as it absorbs from the Sun indicating it also has an internal heat source. Saturn has an [|extensive ring system] which is formed by a thousand individual rings. The rings appear to contain water ice and dust. The thickness of the rings ranges from 10 to 100 meters and the rings vary in brightness. There are [|gaps between some rings], while other rings appear to be braided together. [|Astronomers] believe the rings developed from particles that resulted from the break-up of naturally occurring [|satellites]. The particles in the rings closer to the planet [|orbit] the planet at a faster speed than the particles in the rings farther from the planet. There are satellites within the rings which result in the gaps that are present between some rings. As with Jupiter, the pressurized hydrogen in Saturn's [|mantle] produces electric currents which create a strong [|magnetic field] around the planet. Saturn has at least 53 [|naturally occurring satellites].

The rings of [|Saturn] have puzzled astronomers since Galileo Galilei discovered them with his telescope in 1610. Detailed study by the [|Voyager 1] and [|Voyager 2] spacecraft in the 1980s only increased the mystery. There are billions of ring particles in the entire ring system. The ring particle sizes range from tiny, dust-sized icy grains to a few particles as large as mountains. Two tiny moons orbit in gaps (Encke and Keeler gaps) in the rings and keep the gaps open. Other particles (10s to 100s of meters) are too tiny to see, but create propeller-shaped objects in the rings that let us know they are there. The rings are believed to be pieces of [|comets], [|asteroids] or shattered moons that broke up before they reached the planet. Each ring orbits at a different speed around the planet. Information from NASA's [|Cassini] mission will help reveal how they formed, how they maintain their orbit and, above all, why they are there in the first place. While the other three gas planets in the solar system -- [|Jupiter], [|Uranus] and [|Neptune] -- have rings orbiting around them, Saturn's are by far the largest and most spectacular. With a thickness of about one kilometer (3,200 feet) or less, they span up to 282,000 km (175,000 miles), about three quarters of the distance between the [|Earth] and its [|Moon]. Named alphabetically in the order they were discovered, the rings are relatively close to each other, with the exception of the Cassini Division, a gap measuring 4,700 km (2,920 miles). The main rings are, working outward from the planet, known as C, B and A. The Cassini Division is the largest gap in the rings and separates Rings B and A. In addition a number of fainter rings have been discovered more recently. The D Ring is exceedingly faint and closest to the planet. The F Ring is a narrow feature just outside the A Ring. Beyond that are two far fainter rings named G and E. The rings show a tremendous amount of structure on all scales; some of this structure is related to gravitational perturbations by Saturn's many moons, but much of it remains unexplained. To enter Saturn's orbit, Cassini flew through the gap between the F and G rings, which is farther from the planet than the Cassini Division. As a safety measure, during the crossing of the ring plane, instruments and cameras onboard the spacecraft were shut off temporarily. However, the spectacular crossing into Saturn's orbit brought incredible information, images and footage. The instruments onboard Cassini are still collecting unique data that may answer many questions about the rings' composition.
 * Reference:** USGS Astrogeology: Gazetteer of Planetary Nomenclature -- Ring Nomenclature

Saturn&apos;s Monster Storm Head Credit: NASA/JPL-Caltech/Space Science Institute The head of Saturn&apos;s huge northern storm is well established in this view captured early in the storm&apos;s development by NASA&apos;s Cassini __[|spacecraft]__ in late 2010.

Saturn&apos;s atmosphere and its rings are shown here in a false color composite made from three images taken in near infrared light through filters that are sensitive to varying degrees of methane absorption. Red and orange colors in this view indicate clouds that are deep in the atmosphere. Yellow and green colors, most noticeable near the top of the view, indicate intermediate clouds. White and blue indicate high clouds and haze. The rings appear as a thin horizontal line of bright blue because they are outside of the atmosphere and not affected by methane absorption.

This view looks toward the southern, unilluminated side of the rings from just below the ringplane.

Saturn is the sixth planet from the [|Sun] and the second [|largest]: [|orbit]: 1,429,400,000 km (9.54 [|AU]) from Sun [|diameter]: 120,536 km (equatorial) [|mass]: 5.68e26 kg

In Roman [|mythology], Saturn is the god of agriculture. The associated Greek god, [|Cronus], was the son of Uranus and Gaia and the father of Zeus (Jupiter). Saturn is the root of the English word "Saturday" (see [|Appendix 5]).

Saturn has been known since prehistoric times. [|Galileo] was the first to observe it with a telescope in 1610; he noted its odd appearance but was confused by it. Early observations of Saturn were complicated by the fact that the Earth passes through the plane of Saturn's [|rings] every few years as Saturn moves in its orbit. A low [|resolution] image of Saturn therefore changes drastically. It was not until 1659 that [|Christiaan Huygens] correctly inferred the geometry of the rings. Saturn's rings remained unique in the known solar system until 1977 when very faint rings were discovered around [|Uranus] (and shortly thereafter around [|Jupiter] and [|Neptune]).

Saturn was first visited by NASA's [|Pioneer 11] in 1979 and later by [|Voyager 1] and [|Voyager 2]. [|Cassini](a joint NASA / ESA project) arrived on July 1, 2004 and will orbit Saturn for at least four years.

Saturn is visibly flattened (oblate) when viewed through a small telescope; its equatorial and polar diameters vary by almost 10% (120,536 km vs. 108,728 km). This is the result of its rapid rotation and fluid state. The other gas planets are also oblate, but not so much so.

Saturn is the least dense of the planets; its specific gravity (0.7) is less than that of water.

Like Jupiter, Saturn is about 75% hydrogen and 25% helium with traces of water, methane, ammonia and "rock", similar to the composition of the primordial [|Solar Nebula]from which the solar system was formed.

Saturn's interior is similar to Jupiter's consisting of a rocky core, a [|liquid metallic hydrogen] layer and a molecular hydrogen layer. Traces of various [|ices]are also present.

Saturn's interior is hot (12000 K at the core) and Saturn radiates more energy into space than it receives from the Sun. Most of the extra energy is generated by the [|Kelvin-Helmholtz mechanism]as in Jupiter. But this may not be sufficient to explain Saturn's luminosity; some additional mechanism may be at work, perhaps the "raining out" of helium deep in Saturn's interior.

The [|bands] so prominent on Jupiter are much fainter on Saturn. They are also much wider near the equator. Details in the cloud tops are invisible from Earth so it was not until the [|Voyager] encounters that any detail of Saturn's atmospheric circulation could be studied. Saturn also exhibits long-lived ovals (red spot at center of image at right) and other features common on Jupiter. In 1990, [|HST]observed an enormous white cloud near Saturn's equator which was not present during the Voyager encounters; in 1994 another, smaller storm was observed (left).

Two prominent rings (A and B) and one faint ring (C) can be seen from the Earth. The gap between the A and B rings is known as the **[|Cassini] division**. The much fainter gap in the outer part of the A ring is known as the **Encke Division** (but this is somewhat of a [|misnomer] since it was very likely never seen by Encke). The [|Voyager] pictures show four additional faint rings. Saturn's rings, unlike the rings of the other planets, are very bright ([|albedo]0.2 - 0.6).

Though they look continuous from the Earth, the rings are actually composed of innumerable small particles each in an independent orbit. They range in size from a centimeter or so to several meters. A few kilometer-sized objects are also likely.

Saturn's rings are extraordinarily thin: though they're 250,000 km or more in diameter they're [|less than one kilometer thick]. Despite their impressive appearance, there's really very little material in the rings -- if the rings were compressed into a single body it would be no more than 100 km across.

The ring particles seem to be composed primarily of water ice, but they may also include rocky particles with icy coatings.

[|Voyager]confirmed the existence of puzzling radial inhomogeneities in the rings called "spokes" which were first reported by amateur astronomers (left). Their nature remains a mystery, but may have something to do with Saturn's magnetic field.

Saturn's outermost ring, the F-ring, is a complex structure made up of several smaller rings along which "knots" are visible. Scientists speculate that the knots may be clumps of ring material, or mini moons. The strange braided appearance visible in the Voyager 1 images (right) is not seen in the Voyager 2 images perhaps because Voyager 2 imaged regions where the component rings are roughly parallel. They are prominent in the [|Cassini images]which also show some as yet unexplained wispy spiral structures.

There are complex tidal [|resonances] between some of Saturn's moons and the ring system: some of the moons, the so-called [|"shepherding satellites"] (i.e. [|Atlas], [|Prometheus] and [|Pandora]) are clearly important in keeping the rings in place; [|Mimas] seems to be responsible for the paucity of material in the [|Cassini] division, which seems to be similar to the [|Kirkwood gaps] in the asteroid belt; [|Pan] is located inside the Encke Division and [|S/2005 S1]is in the center of the Keeler Gap. The whole system is very complex and as yet poorly understood.

The origin of the rings of Saturn (and the other jovian planets) is unknown. Though they may have had rings since their formation, the ring systems are not stable and must be regenerated by ongoing processes, perhaps the breakup of larger satellites. The current set of rings may be only a few hundred million years old.

Like the other jovian planets, Saturn has a significant magnetic field.

When it is in the nighttime sky, Saturn is easily [|visible] to the unaided eye. Though it is not nearly as bright as Jupiter, it is easy to identify as a planet because it doesn't "twinkle" like the stars do. The rings and the larger satellites are visible with a small astronomical telescope. There are several [|Web sites] that show the current position of Saturn (and the other planets) in the sky. More detailed and customized charts can be created with a [|planetarium program].

Saturn's Satellites
Saturn has 53 named satellites (as of spring 2010):
 * ==The three pairs Mimas-Tethys, Enceladus-Dione and Titan-Hyperion interact gravitationally in such a way as to maintain stable relationships between their orbits: the period of Mimas' orbit is exactly half that of [|Tethys], they are thus said to be in a 1:2 [|resonance]; [|Enceladus]-[|Dione] are also 1:2; [|Titan]-[|Hyperion]are in a 3:4 resonance.==
 * See [|Scott Sheppard's site]for the latest about recently discovered moons (there are lots).
 * There are 9 more that have been discovered but as yet not named.

Read more about [|Saturn l Saturn facts, pictures and information.] by [|nineplanets.org]