Saturn

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Orbital characteristics (Epoch J2000)
Semi-major axis	1,426,725,413 km 9.537 070 32 AU
Orbital circumference	8.958 Tm 59.879 AU
Eccentricity	0.054 150 60
Perihelion	1,349,467,375 km 9.020 632 24 AU
Aphelion	1,503,983,449 km 10.053 508 40 AU
Orbital period	10,757.7365 d (29.45 a)
Synodic period	378.09 d
Avg. Orbital Speed	9.638 km/s
Max. Orbital Speed	10.182 km/s
Min. Orbital Speed	9.136 km/s
Inclination	2.484 46° (5.51° to Sun's equator)
Longitude of the ascending node	113.715 04°
Argument of the perihelion	338.716 90°
Number of satellites	49 confirmed
Physical characteristics
Equatorial diameter	120,536 km [1] (9.449 Earths)
Polar diameter	108,728 km (8.552 Earths)
Oblateness	0.097 96
Surface area	4.27×1010 km2 (83.703 Earths)
Volume	7.46×1014 km3 (688.79 Earths)
Mass	5.6846×1026 kg (95.162 Earths)
Mean density	0.6873 g/cm3 (less than water)
Equatorial gravity	8.96 m/s2 (0.914 gee)
Escape velocity	35.49 km/s
Rotation period	0.444 009 259 2 d (10 h 39 min 22.400 00 s) 1
Rotation velocity	9.87 km/s = 35,500 km/h (at the equator)
Axial tilt	26.73°
Right ascension of North pole	40.59° (2 h 42 min 21 s)
Declination	83.54°
Albedo	0.47
Avg. Cloudtop temp.	93 K
Surface temp.	min mean max 82 K 143 K N/A K
Atmospheric characteristics
Atmospheric pressure	140 kPa
Hydrogen	>93%
Helium	>5%
Methane	0.2%
Water vapor	0.1%
Ammonia	0.01%
Ethane	0.0005%
Phosphine	0.0001%

Saturn is the sixth planet from the Sun. It is a gas giant, the second-largest planet in the solar system after Jupiter. Saturn has large rings consisting of mostly ice particles with a smaller amount of rocky debris. It was named after the Roman god Saturn. Its symbol is a stylized representation of the god's sickle (Unicode: ♄). Download high resolution version (650x813, 21 KB)Original Caption Released with Image: This true color picture was assembled from Voyager 2 Saturn images obtained Aug. ... In physics, an orbit is the path that an object makes, around another object, whilst under the influence of a source of centripetal force, such as gravity. ... In astronomy, an epoch is a moment in time for which celestial coordinates or orbital elements are specified. ... The J2000. ... In geometry, the term semi-major axis (also semimajor axis) is used to describe the dimensions of ellipses and hyperbolas. ... To help compare different distances this page lists lengths starting at 1012 m (1000 million km). ... A kilometre (American spelling: kilometer, symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). ... The astronomical unit (AU or au or a. ... The circumference is the distance around a closed curve. ... Tera (symbol: T) is a prefix in the SI system of units denoting 1012, or 1 000 000 000 000. ... The metre is the basic unit of length in the International System of Units (SI: Système International dUnités). ... (This page refers to eccitricity in astrodynamics. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... This article is about several astronomical terms (apogee & perigee, aphelion & perihelion, generic equivalents based on apsis, and related but rarer terms. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... To help compare orders of magnitude of different times this page lists times between 3. ... A Julian year is the length of an average year in the Julian calendar, 365. ... The orbital period is the time it takes a planet (or another object) to make one full orbit. ... The orbital speed of a body, generally a planet, a natural satellite, an artificial satellite, or a multiple star, is the speed at which it orbits around the barycenter of a system, usually around a more massive body. ... Inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit and is the angular distance of the orbital plane from the plane of the reference (usually planets equator or the ecliptic), stated in degrees. ... The Longitude of the ascending node () is one of the orbital elements used to specify the orbit of an object in space. ... The argument of the perihelion is one of the orbital elements describing the orbit of a planet. ... Moons of solar system scaled to Earths Moon The common noun moon (not capitalized) is used to mean any natural satellite of the other planets. ... The equator is an imaginary line drawn around a planet, halfway between the poles. ... For the geometric term, see diameter. ... To help compare different orders of magnitude, this page lists lengths starting at 108 m (100,000 km). ... For other uses of the word pole, see Pole (disambiguation). ... Oblate also refers to a member of the Roman Catholic religious order of the Missionary Oblates of Mary Immaculate, or in some cases to a lay or religious person who has officially associated himself (or herself) with a monastic community such as the Benedictines for reasons of personal enrichment without... This article explains the meaning of area as a physical quantity. ... Square kilometre (US spelling: Square kilometer), symbol km², is an SI unit of surface area. ... Volume (also called capacity) is a quantification of how much space an object occupies. ... A cubic kilometre (symbol km³) is an SI derived unit of volume. ... Mass is a property of physical objects that, roughly speaking, measures the amount of matter they contain. ... The international prototype, made of platinum-iridium, which is kept at the BIPM under conditions specified by the 1st CGPM in 1889. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... Water (from the Old English word wæter; c. ... It has been suggested that Law of universal gravitation be merged into this article or section. ... Acceleration is the time rate of change of velocity, and at any point on a v-t graph, it is given by the gradient of the tangent to that point In physics, acceleration (symbol: a) is defined as the rate of change (or time derivative) of velocity. ... g (also gee, g-force or g-load) is a non-SI unit of acceleration defined as exactly 9. ... In physics, for a given gravitational field and a given position, the escape velocity is the minimum speed an object without propulsion, at that position, needs to have to move away indefinitely from the source of the field, as opposed to falling back or staying in an orbit within a... Axial tilt is an astronomical term regarding the inclination angle of a planets rotational axis in relation to its orbital plane. ... Right ascension (RA; symbol α: Greek letter alpha) is the astronomical term for one of the two coordinates of a point on the celestial sphere when using the equatorial coordinate system. ... In astronomy declination (dec) is one of the two coordinates of the equatorial coordinate system, the other being either right ascension or hour angle. ... The albedo is a measure of reflectivity of a surface or body. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... To help compare different orders of magnitude this page lists temperatures between 100 kelvins and 1000 kelvins. ... Atmosphere is the general name for a layer of gases that may surround a material body of sufficient mass. ... diurnal (daily) rhythm of air pressure in northern Germany (black curve is air pressure) Atmospheric pressure is the pressure above any area in the Earths atmosphere caused by the weight of air. ... The pascal (symbol Pa) is the SI unit of pressure. ... General Name, Symbol, Number hydrogen, H, 1 Chemical series nonmetals Group, Period, Block 1, 1, s Appearance colorless Atomic mass 1. ... General Name, Symbol, Number helium, He, 2 Chemical series noble gases Group, Period, Block 18, 1, s Appearance colorless Atomic mass 4. ... The simplest hydrocarbon, methane, is a gas with a chemical formula of CH4. ... Water (from the Old English word wæter; c. ... Ammonia is a chemical compound with the formula NH3. ... Ethane is a chemical compound with chemical formula C2H6. ... Phosphine is the common name for phosphorus hydride (PH3), also known by the IUPAC name phosphane. ... A planet (from the Greek πλανήτης, planÄ“tÄ“s which means wanderer or more forcefully vagrant, tramp) is an object in orbit around a star that is not a star in its own right. ... A sun is the star at the center of a planetary system. ... A gas giant is a large planet that is not composed mostly of rock or other solid matter. ... Mosaic of the Solar System planets except Pluto, including Earths Moon (not to scale). ... Atmospheric characteristics Atmospheric pressure 70 kPa Hydrogen ~86% Helium ~14% Methane 0. ... Roman mythology can be considered as two parts. ... Rhea tricking Cronus with a wrapped stone. ... In computing, Unicode provides an international standard which has the goal of providing the means to encode the text of every document people want to store on computers. ...

The Chinese, Korean, and Japanese cultures refer to the planet as the Earth Star, based on the Five Elements. In traditional Chinese philosophy, natural phenomena can be classified into the Five Elements (Chinese: 五行; pinyin: ): wood, fire, earth, metal, and water (木, 火, 土, 金, 水; mù, huǒ, tǔ, jīn, shǔi). ...

Physical characteristics

Saturn's shape is visibly flattened at the poles and bulging at the equator (an oblate spheroid); 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 to a lesser degree. Saturn is also the only one of the Solar System's planets less dense than water, with an average specific density of 0.69. This is only an average value, however; Saturn's upper atmosphere is less dense and its core is considerably more dense than water. Oblate also refers to a member of the Roman Catholic religious order of the Missionary Oblates of Mary Immaculate, or in some cases to a lay or religious person who has officially associated himself (or herself) with a monastic community such as the Benedictines for reasons of personal enrichment without... A spheroid is a quadric surface in three dimensions obtained by rotating an ellipse about one of its principal axes. ...

Saturn's interior is similar to Jupiter's, having a rocky core at the center, a liquid metallic hydrogen layer above that, and a molecular hydrogen layer above that. Traces of various ices are also present. Saturn has a very hot interior, reaching 12000 K at the core, and it radiates 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. Metallic hydrogen results when hydrogen is sufficiently compressed and undergoes a phase change, and it is an example of degenerate matter. ... Molecular hydrogen, H2, is a molecule formed from two atoms of hydrogen. ... The kelvin (symbol: K) is the SI unit of temperature, and is one of the seven SI base units. ... A sun is the star at the center of a planetary system. ... The Kelvin-Helmholtz mechanism is an astronomical event that occurs when the surface of a star or a planet cools. ...

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

Saturn's atmosphere exhibits a banded pattern similar to Jupiter's, but Saturn's bands are much fainter and they're also much wider near the equator. Saturn's 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 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. Astronomers using infrared imaging have shown that Saturn has a warm polar vortex, and is the only planet in the solar system known to do so. Infrared image of saturn showing a warm polar vortex File links The following pages link to this file: Saturn (planet) Categories: NASA images ... Infrared image of saturn showing a warm polar vortex File links The following pages link to this file: Saturn (planet) Categories: NASA images ... Atmosphere is the general name for a layer of gases that may surround a material body of sufficient mass. ... The Voyager spacecraft Launch of Voyager 2 Voyager is also the name of a planned series of unmanned probes to Mars, cancelled in 1968. ... 50 cm refracting telescope at Nice Observatory. ... 1990 is a common year starting on Monday of the Gregorian calendar. ... The Hubble Space Telescope is a telescope in orbit around the Earth. ... 1994 was a common year starting on Saturday of the Gregorian calendar, and was designated the International year of the Family. ... Image of a small dog taken in mid-infrared (thermal) light (false color) Infrared (IR) radiation is electromagnetic radiation of a wavelength longer than visible light, but shorter than microwave radiation. ... Vortex created by the passage of an aircraft wing, revealed by coloured smoke A vortex is a spinning turbulent flow (or any spiral whirling motion) with closed streamlines. ...

Rotational behaviour

Since Saturn does not rotate on its axis at a uniform rate, two rotation periods have been assigned to it, like 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, has a period of 10 h 39 min 22.4 s (810.8°/d); because it is very close in value to System II, it has largely superseded it. A day is any of several different units of time. ...

While approaching Saturn in 2004, the Cassini spacecraft found that the radio rotation period of Saturn had increased slightly, to approximately 10 h 45 m 45 s (± 36 s). [2] The cause of the change is unknown. 2004 is a leap year starting on Thursday of the Gregorian calendar. ... This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. ...

Saturn's rings

Saturn is probably best known for its planetary rings, which make it one of the most visually remarkable objects in the solar system. See rings of Saturn for a list of the planet's rings. A planetary ring is a ring of dust and other small particles orbiting around a planet in a flat disc-shaped region. ... Saturns rings; the major rings are labelled This is a list of the named rings of Saturn, and the gaps between them. ...

History

The rings were first observed by Galileo Galilei in 1610 with his telescope, but he clearly did not know what to make of them. He wrote to the Grand Duke of Tuscany that "Saturn is not alone but is composed of three, which almost touch one another and never move nor change with respect to one another. They are arranged in a line parallel to the zodiac, and the middle one [Saturn itself] is about three times the size of the lateral ones [the edges of the rings]." He also described Saturn as having "ears." In 1612 the plane of the rings was oriented directly at the Earth and the rings appeared to vanish, and then in 1613 they reappeared again, further confusing Galileo. Galileo Galilei (Pisa, February 15, 1564 – Arcetri, January 8, 1642), was a Tuscan astronomer, philosopher, and physicist who is closely associated with the scientific revolution. ... // Events January 7 - Galileo Galilei discovers the Galilean moons of Jupiter. ... 50 cm refracting telescope at Nice Observatory. ... Tuscany (Italian Toscana) is a region in central Italy, bordering on Latium to the south, Umbria to the east, Emilia-Romagna and Liguria to the north, and the Tyrrhenian Sea to the west. ... This article is about the astrological concept. ... Events January 20 - Mathias becomes Holy Roman Emperor. ... Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third planet outward from the Sun. ... Events January - Galileo observes Neptune, but mistakes it for a star and so is not credited with its discovery. ...

The riddle of the rings was not solved until 1655 by Christiaan Huygens, using a telescope much more powerful than the ones available to Galileo in his time. Events New Sweden (Delaware) attacked and captured by Dutch forces. ... Christiaan Huygens Christiaan Huygens (pronounced in English (IPA): ; in Dutch: ) (April 14, 1629–July 8, 1695), was a Dutch mathematician and physicist; born in The Hague as the son of Constantijn Huygens. ...

In 1675 Giovanni Domenico Cassini determined that Saturn's ring was actually composed of multiple smaller rings with gaps between them; the largest of these gaps was later named the Cassini Division. Events January 5 - The Battle of Turckeim August 10 - Building of the Royal Greenwich Observatory began November 11 - Guru Gobind Singh becomes the Tenth Guru of the Sikhs. ... Giovanni Domenico (Jean-Dominique) Cassini Giovanni Domenico Cassini (June 8, 1625 - September 14, 1712) was an Italian-French astronomer and engineer. ...

Physical characteristics of the rings

The rings can be viewed using a quite modest modern telescope or with a good pair of binoculars. They extend from 6,630 km to 120,700 km above Saturn's equator, and are composed of silica rock, iron oxide, and ice particles ranging in size from specks of dust to the size of a small automobile. There are two main theories regarding the origin of Saturn's rings. One theory, originally proposed by Édouard Roche in the 19th century, is that the rings were once a moon of Saturn whose orbit decayed until it came close enough to be ripped apart by tidal forces (see Roche limit). A variation of this theory is that the moon disintegrated after being struck by a large comet or asteroid. The second theory is that the rings were never part of a moon, but are instead left over from the original nebular material that Saturn formed out of. This theory is not widely accepted today, since Saturn's rings are thought to be unstable over periods of millions of years and therefore of relatively recent origin. 50 cm refracting telescope at Nice Observatory. ... Binoculars A set of binoculars (from Latin, bi-, two-, and oculus, eye) is a hand-held tool used to make distant objects appear closer by passing the image through two adjacent series of lenses, and erecting prisms. ... The chemical compound silicon dioxide, also known as silica, is the oxide of silicon, chemical formula SiO2. ... Iron oxide pigment There are a number of iron oxides: Iron oxides Iron(II) oxide or ferrous oxide (FeO) The black-coloured powder in particular can cause explosions as it readily ignites. ... Édouard Albert Roche (1820-1883) was a French scientist. ... Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... The tidal force is a secondary effect of the force of gravity and is responsible for the tides. ... The Roche limit is the distance within which a celestial body held together only by its own gravity will disintegrate due to a second celestial bodys tidal forces exceeding the first bodys gravitational self-attraction. ... Comet Hale-Bopp, showing a white dust tail and blue gas tail (February 1997) A comet is a small astronomical object similar to an asteroid but composed largely of ice. ... An asteroid is a small, solid object in our Solar System, orbiting the Sun. ... The Triangulum Emission Nebula NGC 604 lies in a spiral arm of Galaxy M33, 2. ...

While the largest gaps in the rings, such as the Cassini division and Encke division, could be seen from Earth, the Voyagers discovered the rings to have an intricate structure of thousands of thin gaps and ringlets. This structure is thought to arise from the gravitational pull of Saturn's many moons in several different ways. Some gaps are cleared out by the passage of tiny moonlets such as Pan, many more of which may yet be undiscovered, and some ringlets seem to be maintained by the gravitational effects of small shepherd satellites such as Prometheus and Pandora. Other gaps arise from resonances between the orbital period of particles in the gap and that of a more massive moon further out; Mimas maintains the Cassini division in this manner. Still more structure in the rings actually consists of spiral waves raised by the moons' periodic gravitational perturbations. Categories: Astronomy stubs ... The Encke Division in closeup The Encke Division, also called the Encke Gap, is a perceived gap within Saturns A Ring. ... Pan (pan, Greek Πάν) is a moon of Saturn, named after the god Pan. ... A planetary ring is a ring of dust and other small particles orbiting around a planet in a flat disc-shaped region. ... Prometheus (proe-mee-thee-us, Greek Προμηθέας) is a moon of Saturn. ... Pandora (pan-dor-a, Greek Πανδώρα) is a moon of Saturn. ... In physics, resonance is the tendency of a system to absorb more oscillatory energy when the frequency of the oscillations matches the systems natural frequency of vibration (its resonant frequency) than it does at other frequencies. ... Mimas (mye-mus, Greek Μίμας, Μῑμάντ-) is a moon of Saturn that was discovered in 1789 by William Herschel. ...

Data from the Cassini space probe indicates that the rings of Saturn possess their own atmosphere, independent of that of the planet itself. The atmosphere is composed of molecular oxygen gas (O₂) and is thought to be a product of the disintegration of water ice from the rings into its components, oxygen and hydrogen. [3] General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ...

The dark side of the rings

Compare images from the Cassini spacecraft taken in March and October 2004, and a Pioneer 11 picture from 1979: This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. ... March is the third month of the year in the Gregorian Calendar and one of seven Gregorian months with the length of 31 days. ... October is the tenth month of the year in the Gregorian Calendar and one of seven Gregorian months with the length of 31 days. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... Pioneer 11 at Saturn (artists impression) Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ... 1979 is a common year starting on Monday. ...

Cassini spacecraft: March 27, 2004; Frontlit rings. Notice both the shadow of Saturn on the rings, and the shadow of the rings onto the planet. The thick B ring is the brightest part of the ring system.

Pioneer 11 spacecraft: September 1, 1979; Backlit rings, showing the overall darkness of the rings from this angle. The thickest parts of the rings are almost invisible.

Cassini spacecraft: October 27, 2004; Backlit rings in detail. The thick B ring appears darkest from this side.

The side of Saturn's rings that is lit by the Sun looks very different to the backlit side, which is darker overall and appears almost black in the thick B ring. From Earth, we cannot appreciate this because the Earth cannot view Saturn from an angle that displays the backlit side of the rings, and our only views of it are from spacecraft. In 2004, the Cassini spacecraft revealed the first views of the backlit side in 25 years. CAPTION FROM NASA: Saturn and its rings completely fill the field of view of Cassinis narrow-angle camera in this natural-color image taken on March 27, 2004. ... CAPTION FROM NASA: Saturn and its rings completely fill the field of view of Cassinis narrow-angle camera in this natural-color image taken on March 27, 2004. ... This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. ... March 27 is the 86th day of the year in the Gregorian Calendar (87th in Leap years). ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... Image File history File links NASA Image #79-HC-432 Pioneer 11 - September 1, 1979 One of the first spacecraft views of Saturn was taken by Pioneer 11 three days before its closest encounter. ... Image File history File links NASA Image #79-HC-432 Pioneer 11 - September 1, 1979 One of the first spacecraft views of Saturn was taken by Pioneer 11 three days before its closest encounter. ... Pioneer 11 at Saturn (artists impression) Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ... September 1 is the 244th day of the year (245th in leap years). ... 1979 is a common year starting on Monday. ... Download high resolution version (1024x1024, 118 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (1024x1024, 118 KB) Wikipedia does not have an article with this exact name. ... This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. ... October 27 is the 300th day of the year (301st in leap years) in the Gregorian Calendar, with 65 days remaining. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ...

The spokes of the rings

Spokes in the B ring, imaged by Voyager 2 in 1981.

Until 1980, the structure of the rings of Saturn was explained exclusively as the action of gravitational forces. The Voyager spacecraft found dark radial features in the B ring, called spokes, which could not be explained in this manner, as their persistence and rotation around the rings were not consistent with orbital mechanics. It is assumed that they are connected to electromagnetic interactions, as they rotate almost synchronously with the magnetosphere of Saturn. However, the precise mechanism behind the spokes is still unknown. Image:Voyager ring spokes. ... Image:Voyager ring spokes. ... The Voyager 2 spacecraft was launched in 1977, originally planned as Mariner 12 of the Mariner program. ... 1981 is a common year starting on Thursday of the Gregorian calendar. ... 1980 is a leap year starting on Tuesday. ... This article covers the physics of gravitation. ... This article or section should be merged with Celestial Mechanics Astrodynamics is the study and creation of orbits, especially those of artificial satellites. ... Electromagnetism is the physics of electromagnetic fields: a field, encompassing all of space, comprised of electrical and magnetic fields. ... A magnetosphere is the region around an astronomical object, in which phenomena are dominated by its magnetic field. ...

As of February 2005, the Cassini spacecraft has not observed any spokes in the rings, despite possessing imaging equipment of higher quality than the Voyagers'. It is possible that the spokes appear and disappear seasonally. February is the second month of the year in the Gregorian Calendar. ... 2005 is a common year starting on Saturday of the Gregorian calendar and is the current year. ...

Exploration of Saturn

A Hubble Space Telescope image, captured in October 1996 shows Saturn's rings from just past edge-on

Caption: This Hubble Space Telescope image, captured in October 1996, shows Saturns rings from just past edge-on. ... Caption: This Hubble Space Telescope image, captured in October 1996, shows Saturns rings from just past edge-on. ...

Pioneer 11 flyby

Saturn was first visited by Pioneer 11 in 1979. It flew within 20,000 km the planet's cloudtops. Low-resolution images were acquired of the planet and few of its moons. Resolution was not good enough to discern surface features, however. 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. It also measured the temperature of Titan. [4] Pioneer 11 at Saturn (artists impression) Pioneer 11 was the second mission to investigate Jupiter and the outer solar system and the first to explore the planet Saturn and its main rings. ... 1979 is a common year starting on Monday. ...

Voyager flybys

In November, 1980, Voyager 1 probe visited the Saturn system. It sent back the first high-resolution images of the planet, rings, and the 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 spacecraft's trajectory out from the plane of the solar system. 1980 is a leap year starting on Tuesday. ... A NASA artists rendition of a Voyager spacecraft The Voyager 1 spacecraft is an 815-kilogram unmanned probe of the outer solar system and beyond, launched September 5, 1977, and currently operational. ...

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 camera stuck and some planned imaging was lost. Saturn's gravity was used to direct the spacecraft's trajectory towards Uranus. 1981 is a common year starting on Thursday of the Gregorian calendar. ... The Voyager 2 spacecraft was launched in 1977, originally planned as Mariner 12 of the Mariner program. ...

The probes discovered and confirmed several new satellites orbiting near or within the planet's rings. They also discovered the small Maxwell and Keeler gaps. Image of S/2005 S 1 obtained by Cassini showing the ripples it induces in the edges of the Keeler gap. ...

Cassini orbiter

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. 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 flood of data during the atmospheric descent and after the landing. As of 2005, Cassini is conducting multiple flybys of Titan and icy satellites. The primary mission ends in 2008 when the spacecraft has completed 74 orbits around the planet. July 1 is the 182nd day of the year (183rd in leap years) in the Gregorian Calendar, with 183 days remaining. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... This is an artists concept of Cassini during the Saturn Orbit Insertion (SOI) maneuver, just after the main engine has begun firing. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... For other meanings see Phoebe. ... A scale replica of the probe An artists impression of the Huygens probe as it descends through Titans murky, brownish-orange atmosphere of nitrogen and carbon-based molecules, beaming its findings to the distant Cassini orbiter. ... December 25 is the 359th day of the year (360th in leap years) in the Gregorian Calendar, with 6 days remaining. ... 2004 is a leap year starting on Thursday of the Gregorian calendar. ... January 14 is the 14th day of the year in the Gregorian calendar. ... 2005 is a common year starting on Saturday of the Gregorian calendar and is the current year. ... 2005 is a common year starting on Saturday of the Gregorian calendar and is the current year. ... // Predicted events January-June January 15 - NASAs MESSENGER spacecraft makes the first of three flybys of Mercury. ...

For the latest information and news releases, see Cassini website.

Saturn's moons

Main article: Saturn's natural satellites The Saturnian System (photographic montage) Saturn Rings and Satellites. ...

Saturn has a large number of moons, 49 are currently confirmed, 34 of which have names. The precise figure will never be certain as the orbiting chunks of ice in Saturn's rings are all technically moons, and it is difficult to draw a distinction between a large ring particle and a tiny moon. Saturn's most noteworthy moon is Titan, the only moon in the solar system to have a dense atmosphere. Moons of solar system scaled to Earths Moon The common noun moon (not capitalized) is used to mean any natural satellite of the other planets. ... Titan (tye-tun, Greek Τιτάνας) is the largest moon of Saturn and the second largest moon in the solar system[1], after Jupiters moon Ganymede. ...

Due to the tidal forces of Saturn, the moons are currently not at the same position as they were when they were first formed. The tidal force is a secondary effect of the force of gravity and is responsible for the tides. ...

For a timeline of discovery dates, see Timeline of natural satellites. Timeline of natural satellites in the Solar system by decade of discovery For comparison, discovery dates of Uranus, Neptune and Pluto are also included, as well as the first six asteroids. ...

Best viewing of Saturn

Saturn Oppositions: 2001-2029

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.) In the opposition on January 13, 2005, Saturn appeared at its brightest until 2031, mostly due to a favourable orientation of the rings relative to the Earth. Download high resolution version (642x737, 97 KB)These views demonstrate the 29 year period for oppositions of Saturn and the dramatic changes in the appearance of the rings. ... Download high resolution version (642x737, 97 KB)These views demonstrate the 29 year period for oppositions of Saturn and the dramatic changes in the appearance of the rings. ... Opposition is a term used in positional astronomy and astrology. ... This diagram shows the elongations (or angle) of the Earths position from the Sun. ... A sun is the star at the center of a planetary system. ... Centuries: 20th century - 21st century - 22nd century Decades: 1980s 1990s 2000s 2010s 2020s - 2030s - 2040s 2050s 2060s 2070s 2080s Years: 2026 2027 2028 2029 2030 - 2031 - 2032 2033 2034 2035 2036 Events Perth, Australia: Population expected to hit two millionen:2031 Categories: Years in the future ...

Saturn appears to the naked eye in the night sky as a bright, yellowish star varying usually between magnitude +1 and 0 and takes approximately 29 and a half years to make a complete circuit of the ecliptic against the background constellations of the zodiac. Optical aid (a large pair of binoculars or a telescope) magnifying at least 20X is required to clearly resolve Saturn's rings for most people. The astronomical unit (AU or au or a. ... The angular diameter of an object as seen from a given position is the diameter measured as an angle. ... December 3 is the 337th (in leap years the 338th) day of the year in the Gregorian calendar. ... 2001: A Space Odyssey Dr. Dre 2001 2001 is a common year starting on Monday of the Gregorian calendar. ... December 17 is the 351st day of the year (352nd in leap years) in the Gregorian Calendar. ... 2002 is a common year starting on Tuesday of the Gregorian calendar. ... December 31 is the 365th day of the year (366th in leap years) in the Gregorian Calendar. ... 2003 is a common year starting on Wednesday of the Gregorian calendar. ... January 13 is the 13th day of the year in the Gregorian calendar. ... 2005 is a common year starting on Saturday of the Gregorian calendar and is the current year. ... The plane of the Ecliptic is well seen in this picture from the 1994 lunar prospecting Clementine spacecraft. ... This article is about the astrological concept. ... 50 cm refracting telescope at Nice Observatory. ...

Appearance

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Ephemeris of Saturn

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