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Saturn  Astronomical symbol for Saturn
The planet Saturn
Saturn, as seen by Cassini
Designations
Pronunciation /ˈsætərn/  ( listen)[1]
Adjective Saturnian, cronian
Epoch J2000
Aphelion 1,513,325,783 km
10.115 958 04 AU
Perihelion 1,353,572,956 km
9.048 076 35 AU
Semi-major axis 1,433,449,370 km
9.582 017 20 AU
Eccentricity 0.055 723 219
Orbital period 10,759.22 days
29.4571 yr
24,491.07 Saturn solar days[4]
Synodic period 378.09 days[5]
Average orbital speed 9.69 km/s[5]
Mean anomaly 320.346 750°
Inclination 2.485 240° to Ecliptic
5.51° to Sun’s equator
0.93° to Invariable plane[6]
Longitude of ascending node 113.642 811°
Argument of perihelion 336.013 862°
Satellites ~ 200 observed (61 with secure orbits)
Physical characteristics
Equatorial radius 60,268 ± 4 km[7][8]
9.4492 Earths
Polar radius 54,364 ± 10 km[7][8]
8.5521 Earths
Flattening 0.097 96 ± 0.000 18
Surface area 4.27 × 1010 km²[8][9]
83.703 Earths
Volume 8.2713 × 1014 km³[5][8]
763.59 Earths
Mass 5.6846 × 1026 kg[5]
95.152 Earths
Mean density 0.687 g/cm³[5][8]
(less than water)
Equatorial surface gravity 10.44 m/s²[5][8]
1.065 g
Escape velocity 35.5 km/s[5][8]
Sidereal rotation
period
10.57 hours[10]
(10 hr 34 min)
Equatorial rotation velocity 9.87 km/s[8]
35 500 km/h
Axial tilt 26.73°[5]
North pole right ascension 2 h 42 min 21 s
40.589°[7]
North pole declination 83.537°[7]
Albedo 0.342 (bond)
0.47 (geom.)[5]
Surface temp.
   1 bar level
   0.1 bar
min mean max
134 K[5]
84 K[5]
Apparent magnitude +1.2 to -0.24[11]
Angular diameter 14.5" — 20.1"[5]
(excludes rings)
Atmosphere[5]
Scale height 59.5 km
Composition
~96% Hydrogen (H2)
~3% Helium
~0.4% Methane
~0.01% Ammonia
~0.01% Hydrogen deuteride (HD)
0.000 7% Ethane
Ices:
Ammonia
water
ammonium hydrosulfide(NH4SH)

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn, along with Jupiter, Uranus and Neptune, is classified as a gas giant. Together, these four planets are sometimes referred to as the Jovian, meaning "Jupiter-like", planets.

Saturn is named after the Roman god Saturn, equated to the Greek Kronos (the Titan father of Zeus) the Babylonian Ninurta and to the Hindu Shani. Saturn's symbol represents the god's sickle (Unicode: ).

The planet Saturn is composed of hydrogen, with small proportions of helium and trace elements.[12] The interior consists of a small core of rock and ice, surrounded by a thick layer of metallic hydrogen and a gaseous outer layer. The outer atmosphere is generally bland in appearance, although long-lived features can appear. Wind speeds on Saturn can reach 1,800 km/h, significantly faster than those on Jupiter. Saturn has a planetary magnetic field intermediate in strength between that of Earth and the more powerful field around Jupiter.

Saturn has a prominent system of rings, consisting mostly of ice particles with a smaller amount of rocky debris and dust. Sixty-one known moons orbit the planet, not counting hundreds of "moonlets" within the rings. Titan, Saturn's largest and the Solar System's second largest moon (after Jupiter's Ganymede), is larger than the planet Mercury and is the only moon in the Solar System to possess a significant atmosphere.[13]

Contents

Physical characteristics

A rough comparison of the sizes of Saturn and Earth.

Due to a combination of its lower density, rapid rotation, and fluid state, Saturn is an oblate spheroid; that is, it is flattened at the poles and bulges at the equator. Its equatorial and polar radii differ by almost 10%—60,268 km versus 54,364 km.[5] The other gas planets are also oblate, but to a lesser extent. Saturn is the only planet of the Solar System that is less dense than water. Although Saturn's core is considerably denser than water, the average specific density of the planet is 0.69 g/cm³ due to the gaseous atmosphere. Saturn is only 95 Earth masses,[5] compared to Jupiter, which is 318 times the mass of the Earth[14] but only about 20% larger than Saturn.[15]

Internal structure

Though there is no direct information about Saturn's internal structure, it is thought that its interior is similar to that of Jupiter, having a small rocky core surrounded mostly by hydrogen and helium. The rocky core is similar in composition to the Earth, but denser. Above this, there is a thicker liquid metallic hydrogen layer, followed by a layer of liquid hydrogen and helium, and in the outermost 1000 km a gaseous atmosphere.[16] Traces of various volatile are also present. The core region is estimated to be about 9–22 times the mass of the Earth.[17] Saturn has a very hot interior, reaching 11,700 °C at the core, and it radiates 2.5 times more energy into space than it receives from the Sun. Most of the extra energy is generated by the Kelvin-Helmholtz mechanism (slow gravitational compression), but this alone may not be sufficient to explain Saturn's heat production. An additional proposed mechanism by which Saturn may generate some of its heat is the "raining out" of droplets of helium deep in Saturn's interior, the droplets of helium releasing heat by friction as they fall down through the lighter hydrogen.[18]

Atmosphere

Saturn's temperature emissions: the prominent hot spot at the bottom of the image is at Saturn's south pole.

The outer atmosphere of Saturn consists of about 96.3% molecular hydrogen and 3.25% helium.[19] Trace amounts of ammonia, acetylene, ethane, phosphine, and methane have also been detected.[20] The upper clouds on Saturn are composed of ammonia crystals, while the lower level clouds appear to be composed of either ammonium hydrosulfide (NH4SH) or water.[21] The atmosphere of Saturn is significantly deficient in helium relative to the abundance of the elements in the Sun.

The quantity of elements heavier than helium are not known precisely, but the proportions are assumed to match the primordial abundances from the formation of the Solar System. The total mass of these elements is estimated to be 19–31 times the mass of the Earth, with a significant fraction located in Saturn's core region.[22]

Cloud layers

Saturn's celestial body atmosphere exhibits a banded pattern similar to Jupiter's (the nomenclature is the same), but Saturn's bands are much fainter and are also much wider near the equator. At the bottom, extending for 10 km and with a temperature of -23 °C, is a layer made up of water ice. After that comes a layer of ammonium hydrosulfide ice, which extends for another 50 km and is approximately at -93 °C. Eighty kilometers above that are ammonia ice clouds, where the temperatures are about -153 °C. Near the top, extending for some 200 km to 270 km above the clouds, come layers of visible cloud tops and a hydrogen and helium atmosphere.[23] Saturn's winds are among the Solar System's fastest. Voyager data indicate peak easterly winds of 500 m/s (1800 km/h).[12] Saturn's finer cloud patterns were not observed until the Voyager flybys. Since then, however, Earth-based telescopy has improved to the point where regular observations can be made.

Saturn's northern hemisphere, as seen by Cassini. Note the planet's blue appearance through the ring.

Saturn's usually bland atmosphere occasionally exhibits long-lived ovals and other features common on Jupiter. In 1990, the Hubble Space Telescope observed an enormous white cloud near Saturn's equator which was not present during the Voyager encounters, and, in 1994, another smaller storm was observed. The 1990 storm was an example of a Great White Spot, a unique but short-lived phenomenon which occurs once every Saturnian year, or roughly every 30 Earth years, around the time of the northern hemisphere's summer solstice.[24] Previous Great White Spots were observed in 1876, 1903, 1933, and 1960, with the 1933 storm being the most famous. If the periodicity is maintained, another storm will occur in about 2020.[25]

In recent images from the Cassini spacecraft, Saturn's northern hemisphere appears a bright blue, similar to Uranus, as can be seen in the image below. This blue color cannot currently be observed from Earth, because Saturn's rings are currently blocking its northern hemisphere. The color is most likely caused by Rayleigh scattering.

[26]

Astronomers using infrared imaging have shown that Saturn has a warm polar vortex and that it is the only such feature known in the solar system. This, they say, is the warmest spot on Saturn. Whereas temperatures on Saturn are normally -185 °C, temperatures on the vortex often reach as high as -122 °C.[27]

North pole hexagon cloud pattern

A persisting hexagonal wave pattern around the north polar vortex in the atmosphere at about 78°N was first noted in the Voyager images.[28][29] Unlike the north pole, HST imaging of the south polar region indicates the presence of a jet stream, but no strong polar vortex nor any hexagonal standing wave.[30] However, NASA reported in November 2006 that the Cassini spacecraft observed a 'hurricane-like' storm locked to the south pole that had a clearly defined eyewall.[31] This observation is particularly notable because eyewall clouds had not previously been seen on any planet other than Earth (including a failure to observe an eyewall in the Great Red Spot of Jupiter by the Galileo spacecraft).[32]

The straight sides of the northern polar hexagon are each about 13 800 km long. The entire structure rotates with a period of 10h 39 m 24s, the same period as that of the planet's radio emissions, which is assumed to be equal to the period of rotation of Saturn's interior. The hexagonal feature does not shift in longitude like the other clouds in the visible atmosphere.

The pattern's origin is a matter of much speculation. Most astronomers seem to think it was casued by some standing-wave pattern in the atmosphere; but the hexagon might be a novel aurora. Polygonal shapes have been replicated in spinning buckets of fluid in a laboratory.[33]

Magnetosphere

Photo of Saturn by Hubble showing both polar aurorae

Saturn has an intrinsic magnetic field that has a simple, symmetric shape—a magnetic dipole. Its strength at the equator—0.2 gauss (20 µT)—is approximately one twentieth than that of the field around Jupiter and slightly weaker than Earth's magnetic field.[34] As a result the cronian magnetosphere is much smaller than the jovian and extends slightly beyond the orbit of Titan.[35] Most probably, the magnetic field is generated similarly to that of Jupiter—by currents in the metallic-hydrogen layer, which is called a metallic-hydrogen dynamo.[35] Similarly to those of other planets, this magnetosphere is efficient at deflecting the solar wind particles from the Sun. The moon Titan orbits within the outer part of Saturn's magnetosphere and contributes plasma from the ionized particles in Titan's outer atmosphere.[34]

Orbit and rotation

The average distance between Saturn and the Sun is over 1 400 000 000 km (9 AU). With an average orbital speed of 9.69 km/s,[5] it takes Saturn 10 759 Earth days (or about 29½ years), to finish one revolution around the Sun.[5] The elliptical orbit of Saturn is inclined 2.48° relative to the orbital plane of the Earth.[5] Because of an eccentricity of 0.056, the distance between Saturn and the Sun varies by approximately 155 000 000 km between perihelion and aphelion,[5] which are the nearest and most distant points of the planet along its orbital path, respectively.

The visible features on Saturn rotate at different rates depending on latitude, and multiple rotation periods have been assigned to various regions (as in Jupiter's case): System I has a period of 10 h 14 min 00 s (844.3°/d) and encompasses the Equatorial Zone, which extends from the northern edge of the South Equatorial Belt to the southern edge of the North Equatorial Belt. All other Saturnian latitudes have been assigned a rotation period of 10 h 39 min 24 s (810.76°/d), which is System II. System III, based on radio emissions from the planet in the period of the Voyager flybys, has a period of 10 h 39 min 22.4 s (810.8°/d); because it is very close to System II, it has largely superseded it.

However, a precise value for the rotation period of the interior remains elusive. While approaching Saturn in 2004, the Cassini spacecraft found that the radio rotation period of Saturn had increased appreciably, to approximately 10 h 45 m 45 s (± 36 s).[36] The cause of the change is unknown—it was thought to be due to a movement of the radio source to a different latitude inside Saturn, with a different rotational period, rather than because of a change in Saturn's rotation.

Later, in March 2007, it was found that the rotation of the radio emissions did not trace the rotation of the planet, but rather is produced by convection of the plasma disc, which is dependent also on other factors besides the planet's rotation. It was reported that the variance in measured rotation periods may be caused by geyser activity on Saturn's moon Enceladus. The water vapor emitted into Saturn's orbit by this activity becomes charged and "weighs down" Saturn's magnetic field, slowing its rotation slightly relative to the rotation of the planet. At the time it was stated that there is no currently known method of determining the rotation rate of Saturn's core.[37][38][39]

The latest estimate of Saturn's rotation based on a compilation of various measurements from the Cassini, Voyager and Pioneer probes was reported in September 2007 is 10 hours, 32 minutes, 35 seconds.[40]

Planetary rings

The rings of Saturn (imaged here by Cassini in 2007) are the most conspicuous in the Solar System.[16]
Artist's impression of the Phoebe ring, which dwarfs the main rings.

Saturn is probably best known for its system of planetary rings, which makes it the most visually remarkable object in the solar system.[16] They extend from 6 630 km to 120 700 km above Saturn's equator, average approximately 20 meters in thickness, and are composed of 93 percent water ice with a smattering of tholin impurities, and 7 percent amorphous carbon.[41] The particles that make up the rings range in size from specks of dust to the size of a small automobile.[42] There are two main theories regarding the origin of Saturn's rings. One theory is that the rings are remnants of a destroyed moon of Saturn. The second theory is that the rings are left over from the original nebular material from which Saturn formed.

On 6 October 2009, the discovery was announced of a tenuous outer disk of material that is in the plane of Phoebe's orbit, which is tilted 27 degrees from Saturn's equatorial plane.[43] The ring is from 128 to 207 times the radius of Saturn, and is thought to originate from micrometeoroid impacts on Phoebe, which orbits at an average distance of 215 Saturn radii. The ring material should thus share Phoebe's retrograde orbital motion, and after migrating inward would encounter Iapetus's leading face, which could help explain the dramatic two-faced nature of this satellite. While the infalling material cannot be directly responsible for the observed pattern of light and dark regions on Iapetus, it is believed to have initiated a runaway thermal self-segregation process in which ice sublimes from warmer regions and condenses onto cooler regions. This leaves contrasting areas of dark ice-depleted residue and bright ice deposits.[44][45][46]

Natural satellites

Four of Saturn's moons: Dione, Titan, Prometheus (edge of rings), Telesto (top center)

Saturn has at least 62 moons. Titan, the largest, comprises more than 90 percent of the mass in orbit around Saturn, including the rings.[47] Saturn's second largest moon Rhea may have a tenuous ring system of its own.[48] Many of the other moons are very small: 34 are less than 10 km in diameter, and another 14 less than 50 km.[49] Traditionally, most of Saturn's moons have been named after Titans of Greek mythology.

History and exploration

There are three main phases of observation and exploration of Saturn. The first era was ancient observations (such as with the naked eye), before the invention of the modern telescopes. Starting in the 1600s progressively more advanced telescopic observations from earth have been made. The other type is visitation by spacecraft, either by orbiting or flyby. In the 21st century observations continue from the earth (or earth orbiting observatories), and from the Cassini orbiter at Saturn.

Ancient observations

Saturn has been known since prehistoric times.[50] In ancient times, it was the most distant of the five known planets in the solar system (excluding Earth) and thus a major character in various mythologies. In ancient Roman mythology, the god Saturnus, from which the planet takes its name, was the god of the agricultural and harvest sector.[51] The Romans considered Saturnus the equivalent of the Greek god Kronos.[51] The Greeks had made the outermost planet sacred to Kronos,[52] and the Romans followed suit.

In Hindu astrology, there are nine astrological objects, known as Navagrahas. Saturn, one of them, is known as "Sani" or "Shani," the Judge among all the planets, and by everyone accordingly to their own performed deeds bad or good.[51] Ancient Chinese and Japanese culture designated the planet Saturn as the earth star (土星). This was based on Five Elements which were traditionally used to classify natural elements.[53] In ancient Hebrew, Saturn is called 'Shabbathai'. Its angel is Cassiel. Its intelligence, or beneficial spirit, is Agiel (layga), and its spirit (darker aspect) is Zazel (lzaz). In Ottoman Turkish, Urdu and Malay, its name is 'Zuhal', derived from Arabic زحل.

In the 2nd millenium BCE, Babylonian astronomers had begun systematically observing and recording the movements of Saturn.[54] In the 5th century CE, the Indian astronomical text Surya Siddhanta estimated the diameter of Saturn as 73,882 miles, an error of less than 1% from the currently accepted value of 74,580 miles. However, this estimate was based upon an inaccurate guess of the planet's angular diameter as 2.5 arcminutes. The result may have been influenced by the measurements of the Roman-Egyptian astronomer Ptolemy, who found a value of 1.74 arcminutes. This is close to the resolution of the human eye and is significantly larger than the value later obtained by telescope.[55] In the 8th century, the Islamic astronomer, Yaqūb ibn Tāriq, estimated Saturn's diameter as 19 times the Earth radius, equivalent to Saturn's radius being 9.5 times the Earth's radius,[56] which comes close to the currently accepted value of 9.45 times the Earth's radius.[7]

European Observations 1600-1800s

Robert Hooke noted the shadows (a and b) cast by both the globe and the rings on each other in this drawing of Saturn in 1666.

Saturn's rings require at least a 15 mm diameter telescope[57] to resolve and thus were not known to exist until Galileo first saw them in 1610.[58] He thought of them as two moons on Saturn's sides. It was not until Christian Huygens used greater telescopic magnification that this notion was refuted. Huygens also discovered Saturn's moon Titan. Some time later, Giovanni Domenico Cassini discovered four other moons: Iapetus, Rhea, Tethys, and Dione. In 1675, Cassini also discovered the gap now known as the Cassini Division.[59]

No further discoveries of significance were made until 1789 when William Herschel discovered two further moons, Mimas and Enceladus. The irregularly shaped satellite Hyperion, which has a resonance with Titan, was discovered in 1848 by a British team.

In 1899 William Henry Pickering discovered Phoebe, a highly irregular satellite that does not rotate synchronously with Saturn as the larger moons do. Phoebe was the first such satellite found, and it takes more than a year to orbit Saturn in a retrograde orbit. During the early twentieth century, research on Titan led to the confirmation in 1944 that it had a thick atmosphere—a feature unique among the solar system's moons.

20th and 21st Century NASA/ESA probes

Pioneer 11 flyby

Saturn was first visited by Pioneer 11 in September 1979. It flew within 20 000 km of the planet's cloud tops. Low resolution images were acquired of the planet and a few of its moons; the resolution of the images was not good enough to discern surface features. The spacecraft also studied the rings; among the discoveries were the thin F-ring and the fact that dark gaps in the rings are bright when viewed towards the Sun, or in other words, they are not empty of material. Pioneer 11 also measured the temperature of Titan.[60]

Voyager flybys

In November 1980, the Voyager 1 probe visited the Saturn system. It sent back the first high-resolution images of the planet, rings, and satellites. Surface features of various moons were seen for the first time. Voyager 1 performed a close flyby of Titan, greatly increasing our knowledge of the atmosphere of the moon. However, it also proved that Titan's atmosphere is impenetrable in visible wavelengths; so, no surface details were seen. The flyby also changed the spacecraft's trajectory out from the plane of the solar system.[61]

Almost a year later, in August 1981, Voyager 2 continued the study of the Saturn system. More close-up images of Saturn's moons were acquired, as well as evidence of changes in the atmosphere and the rings. Unfortunately, during the flyby, the probe's turnable camera platform stuck for a couple of days, and some planned imaging was lost. Saturn's gravity was used to direct the spacecraft's trajectory towards Uranus.[61]

The probes discovered and confirmed several new satellites orbiting near or within the planet's rings. They also discovered the small Maxwell gap (a gap within the C Ring) and Keeler gap (a 42 km wide gap in the A Ring).

Cassini-Huygens spacecraft

Saturn eclipses the Sun, as seen from Cassini.

On July 1, 2004, the Cassini–Huygens spacecraft performed the SOI (Saturn Orbit Insertion) maneuver and entered into orbit around Saturn. Before the SOI, Cassini had already studied the system extensively. In June 2004, it had conducted a close flyby of Phoebe, sending back high-resolution images and data.

Cassini's flyby of Saturn's largest moon, Titan, has captured radar images of large lakes and their coastlines with numerous islands and mountains. The orbiter completed two Titan flybys before releasing the Huygens probe on December 25, 2004. Huygens descended onto the surface of Titan on January 14, 2005, sending a flood of data during the atmospheric descent and after the landing. During 2005, Cassini conducted multiple flybys of Titan and icy satellites. Cassini's last Titan flyby started on March 23, 2008.

Since early 2005, scientists have been tracking lightning on Saturn, primarily found by Cassini. The power of the lightning is said to be approximately 1000 times that of lightning on Earth. In addition, scientists believe that the storm associated with it is the strongest of its kind ever seen.[62]

On March 10, 2006, NASA reported that, through images, the Cassini probe found evidence of liquid water reservoirs that erupt in geysers on Saturn's moon Enceladus. Images had also shown particles of water in its liquid state emitted by icy jets and towering plumes. According to Dr. Andrew Ingersoll, California Institute of Technology, "Other moons in the solar system have liquid-water oceans covered by kilometers of icy crust. What's different here is that pockets of liquid water may be no more than tens of meters below the surface."[63]

On September 20, 2006, a Cassini probe photograph revealed a previously undiscovered planetary ring, outside the brighter main rings of Saturn and inside the G and E rings. Apparently, the source of this ring is the result of the crashing of a meteoroid off two of the moons of Saturn.[64]

In July 2006, Cassini saw the first proof of hydrocarbon lakes near Titan's north pole, which was confirmed in January 2007. In March 2007, additional images near Titan's north pole discovered hydrocarbon "seas", the largest of which is almost the size of the Caspian Sea.[65]

In October 2006, the probe detected a 8,000 km diameter hurricane with an eyewall at Saturn's South Pole.[66]

From 2004 to November 2, 2009, the probe has discovered and confirmed 8 new satellites. Its primary mission ended in 2008 when the spacecraft had completed 74 orbits around the planet. The probe is now in its first mission extension.

Best viewing

Saturn is the most distant of the five planets easily visible to the naked eye, the other four being Mercury, Venus, Mars, and Jupiter (Uranus and occasionally 4 Vesta are visible to the naked eye in very dark skies), and was the last planet known to early astronomers until Uranus was discovered in 1781. Saturn appears to the naked eye in the night sky as a bright, yellowish point of light whose magnitude is usually between +1 and 0 and takes approximately 29½ years to make a complete circuit of the ecliptic against the background constellations of the zodiac. Most people will require optical aid (large binoculars or a telescope) magnifying at least 20X to clearly resolve Saturn's rings.[16]

While it is a rewarding target for observation for most of the time it is visible in the sky, Saturn and its rings are best seen when the planet is at or near opposition (the configuration of a planet when it is at an elongation of 180° and thus appears opposite the Sun in the sky). During the opposition of December 17, 2002, Saturn appeared at its brightest due to a favorable orientation of its rings relative to the Earth.[67]

In culture

In astrology, Saturn (Saturn symbol.svg) is the ruling planet of Capricorn and, traditionally, Aquarius.

Saturnalia is an Ancient Roman festival that was held in honor of the god Saturn.

Saturn, the Bringer of Old Age is a movement in Gustav Holst's The Planets

Operation Saturn, was a Red Army operation on the Eastern Front of World War II that led to battles in the northern Caucasus and Donets Basin regions of the Soviet Union from December 1942 to February 1943.

The Saturn family of rockets were developed by a team of mostly German rocket scientists led by Wernher von Braun to launch heavy payloads to Earth orbit and beyond. Originally proposed as a military satellite launcher, they were adopted as the launch vehicles for the Apollo program.

Saturn Corporation is an automobile manufacturer and marque, established on January 7, 1985 as a subsidiary of General Motors in response to the success of Japanese automobile imports in the United States.[68]

Saturn Electronics Corporation is a PCB Manufacturing firm based in Romulus, Michigan, United States which was founded in 1985.

Saturn is a German chain of electronics stores, now found in several European countries. Saturn sells household appliances, home entertainment, and media such as CDs and DVDs.

See also

References

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  26. ^ Watanabe, Susan (March 27, 2007). "Saturn's Strange Hexagon". NASA. http://www.nasa.gov/mission_pages/cassini/multimedia/pia09188.html. Retrieved 2007-07-06. 
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  28. ^ Godfrey. "A hexagonal feature around Saturn's North Pole". Icarus. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1988Icar...76..335G&db_key=AST&data_type=HTML&format=. Retrieved 2007-07-09. 
  29. ^ Sanchez-Lavega, A.. "Ground-based observations of Saturn's north polar SPOT and hexagon". Bulletin of the American Astronomical Society. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1993Sci...260..329S&db_key=AST&data_type=HTML&format=. Retrieved 2007-07-30. 
  30. ^ "Hubble Space Telescope Observations of the Atmospheric Dynamics in Saturn's South Pole from 1997 to 2002". The American Astronomical Society. October 8, 2002. http://www.aas.org/publications/baas/v34n3/dps2002/10.htm. Retrieved 2007-07-06. 
  31. ^ "NASA catalog page for image PIA09187". NASA Planetary Photojournal. http://photojournal.jpl.nasa.gov/catalog/PIA09187. Retrieved 2007-05-23. 
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  33. ^ "Geometric whirlpools revealed". Nature. May 19, 2006. http://www.nature.com/news/2006/060519/full/news060515-17.html. Retrieved April 27 2007.  Bizarre geometric shapes that appear at the centre of swirling vortices in planetary atmospheres might be explained by a simple experiment with a bucket of water but correlating this to Saturn's pattern is by no means certain.
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  36. ^ "Scientists Find That Saturn's Rotation Period is a Puzzle". NASA. June 28, 2004. http://www.nasa.gov/mission_pages/cassini/media/cassini-062804.html. Retrieved 2007-03-22. 
  37. ^ NASA Jet Propulsion Laboratory (March 22, 2007). "Enceladus Geysers Mask the Length of Saturn's Day". Press release. http://saturn.jpl.nasa.gov/news/press-release-details.cfm?newsID=733. Retrieved 2007-03-22. 
  38. ^ "The Variable Rotation Period of the Inner Region of Saturn's Plasma Disk". Science. March 22, 2007. http://www.sciencemag.org/cgi/content/abstract/316/5823/442. Retrieved 2007-04-24. 
  39. ^ "A New Spin on Saturn's Rotation". Science. April 20, 2007. http://www.sciencemag.org/cgi/content/abstract/316/5823/442. Retrieved 2007-04-24. 
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  41. ^ Poulet F.; Cuzzi J.N. (2002). "The Composition of Saturn's Rings". NASA Ames Research Center. http://www.ingentaconnect.com/content/ap/is/2002/00000160/00000002/art06967. Retrieved 2007-07-28. 
  42. ^ Shafiq, Muhammad (2005). "Dusty Plasma Response to a Moving Test Change" (PDF). http://www.ee.kth.se/php/modules/publications/reports/2005/TRITA-ALP-2005-03.pdf. Retrieved 2007-07-25. 
  43. ^ Largest known planetary ring discovered, Science News
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  45. ^ Denk, T.; et al. (2009-12-10). "Iapetus: Unique Surface Properties and a Global Color Dichotomy from Cassini Imaging". Science (AAAS) 326. doi:10.1126/science.1177088. http://www.sciencemag.org/cgi/content/abstract/science.1177088. Retrieved 2009-12-19. 
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Further reading

  • Lovett, L.; Horvath, J.; Cuzzi, J. (2006). Saturn: A New View. New York: Harry N. Abrams, Inc.. ISBN 0810930900. 
  • Karttunen, H.; Kröger, P.; et al. (2007). Fundamental Astronomy. New York: Springer, 5th edition. ISBN 3540341439. 

External links

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Travel guide

Up to date as of January 14, 2010

From Wikitravel

Contents

Saturn is a beachtown in the Black Sea Coast region of Romania that was built during the communist period.

Eat

Eating is very cheap by western European standards.

Drink

The town is very noisy till late night with disco and music bands.

Sleep

There are a number of large, old fashioned concrete hotels that were built in the 1960s. Room rates are around 30 euro.

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Source material

Up to date as of January 22, 2010

From Wikisource

Saturn
disambiguation
This is a disambiguation page, which lists works which share the same title. If an article link referred you here, please consider editing it to point directly to the intended page.


Saturn may refer to:


1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

There is more than one meaning of Saturn discussed in the 1911 Encyclopedia. We are planning to let all links go to the correct meaning directly, but for now you will have to search it out from the list below by yourself. If you want to change the link that led you here yourself, it would be appreciated.


Wiktionary

Up to date as of January 14, 2010

Definition from Wiktionary, a free dictionary

Contents

English

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Wikipedia has an article on:

Wikipedia

Etymology

From Old English Sætern, from Latin Saturnus, probably of etruscan origin, plausibly influence by Latin satus, the past participle of serere "to sow"

Pronunciation

  •  audio (US)help, file
  • IPA: /ˈsæ.tɝn/
  • Schoolbook Phonetics: (săʹtûrn)
  • Last Resort Phonetics: SA(T)-turn

Proper noun

Singular
Saturn

Plural
-

Saturn

  1. (Roman mythology) The god of fertility and agriculture, equivalent to the Greek Kronos.
  2. (astronomy) The second largest planet in Earth's solar system, famous for its large rings and until recent times the furthest known; represented in astronomy and astrology by .

Derived terms

Related terms

Translations

The translations below need to be checked and inserted above into the appropriate translation tables, removing any numbers. Numbers do not necessarily match those in definitions. See instructions at Help:How to check translations.

See also

Anagrams


Albanian

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Albanian Wikipedia has an article on:
Saturni

Wikipedia sq

Pronunciation

  • IPA: [satuɾn]

Noun

Saturn m. (uncountable, definite form Saturni)

  1. Saturn

Bosnian

Proper noun

Saturn m.

  1. Saturn

Crimean Tatar

Noun

Saturn (more common name is Zual)

  1. Saturn (planet)

Declension

References

  • Useinov & Mireev Dictionary, Simferopol, Dolya, 2002 [1]

Czech

Proper noun

Saturn m.

  1. Saturn (god)
  2. Saturn (planet)

Estonian

Proper noun

Saturn

  1. Saturn (planet)

See also


German

Pronunciation

Noun

Saturn m.

  1. Saturn, a Roman god
  2. Saturn, a planet in the Solar System

Norwegian

Proper noun

Saturn m.

  1. Saturn (Roman god)
  2. Saturn (planet)

Polish

Noun

Saturn m.

  1. Saturn, a Roman god
  2. Saturn, a planet in the Solar System

Declension

Singular only
Nominative Saturn
Genitive Saturna
Dative Saturnowi
Accusative Saturna
Instrumental Saturnem
Locative Saturnie
Vocative Saturnie

Serbian

Proper noun

Saturn m.

  1. Saturn

See also


Tatar

Noun

Saturn

  1. Saturn (planet)

Declension

References


Strategy wiki

Up to date as of January 23, 2010

From StrategyWiki, the free strategy guide and walkthrough wiki

stub

This page is a stub. Help us expand it, and you get a cookie.

Saturn
Box artwork for Saturn.
Developer(s) Jaleco
Publisher(s) Jaleco
Release date(s)
Genre(s) Shooter
System(s) Arcade
Players 1–2
For the gaming console, see Sega Saturn.

Table of Contents

Saturn/Table of Contents


Gaming

Up to date as of January 31, 2010
(Redirected to Sega Saturn article)

From Wikia Gaming, your source for walkthroughs, games, guides, and more!

Sega Saturn
Manufacturer Sega
Type Console
Release Date November 22, 1994 (JP)

May 11, 1995 (NA)
July 8, 1995 (EU)

Media CD-ROM
Save Format
Input Options Controller
Special Features
Units Sold 10 million worldwide
Top Selling Game Virtua Fighter 2
Variants
Competitor(s) PlayStation
Nintendo 64
Predecessor Sega Genesis, Sega CD
Successor Sega Dreamcast


The Sega Saturn was a console released by Sega in Japan on the November 22, 1994. It is generally seen as an (undeserved, in some eyes) failure, being totally outplayed in the market by the Sony Playstation. It was released in Japan on November 22 1994, in the United States on May 11 1995, and in Europe on July 8 1995. Though originally scheduled to be released in America in September 1995, Sega of America moved the release date earlier in the hopes of cashing in on sales that would have went to the purchase of a Sony PlayStation, which made its debut in America in September 1995.

The Saturn contained a 32-bit video card. Games were released on CD-ROMs. It is followed by the Dreamcast. The Saturn was the first Segas video game console which can display 3D graphics.

In Japan, advertising for the Saturn was frequently provided by cult-favorite Segata Sanshiro.

Stub
This article is a stub. You can help by adding to it.

Stubs are articles that writers have begun work on, but are not yet complete enough to be considered finished articles.


This article uses material from the "Sega Saturn" article on the Gaming wiki at Wikia and is licensed under the Creative Commons Attribution-Share Alike License.







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