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| {{other uses|Tethys (disambiguation)}}
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| {{Infobox planet
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| | name = Tethys
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| | pronounced = {{IPAc-en|ˈ|t|iː|θ|ɨ|s}} or {{IPAc-en|ˈ|t|ɛ|θ|ɨ|s}}{{efn|name=dict-def}}
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| | alt_names = Saturn III
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| | adjectives = Tethyan
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| | image = [[File:Inset-sat tethys-large.jpg|300px]]
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| | caption = Tethys image from ''Voyager 2'' in 1981, with the giant trough [[Ithaca Chasma]] extending diagonally down and left from prominent crater Telemachus at upper right. Smooth plains of the trailing hemisphere, with a reduced crater density, are visible at lower right.
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| | discovery = yes
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| | discoverer = [[Giovanni Domenico Cassini|G. D. Cassini]]
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| | discovered = March 21, 1684
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| | semimajor = {{val|294619|u=km}} <!-- Computed using http://cfa-www.harvard.edu/iau/NatSats/NaturalSatellites.html µ value -->
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| | eccentricity = {{val|0.0001}}{{sfn|Jacobson 2010 SAT339}}<ref name="NASACelestia" />
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| | period = {{val|1.887802|u=[[day|d]]}}<ref name="NASACelestia" />
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| | inclination = 1.12° (to Saturn's equator)
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| | satellite_of = [[Saturn]]
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| | physical_characteristics = yes
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| | dimensions = 1076.8 × 1057.4 × 1052.6 km{{sfn|Roatsch Jaumann et al.|2009|p=765|loc=Tables 24.1–2}}
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| | mean_radius = {{val|531.1|0.6|u=km}} (0.083 Earths){{sfn|Roatsch Jaumann et al.|2009|p=765|loc=Tables 24.1–2}}
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| | mass = {{val|6.17449|0.00132|e=20|u=kg}}{{sfn|Jacobson Antreasian et al.|2006}} (1.03{{e|-4}} Earths)
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| | density = {{val|0.984|0.003|u=g/cm³}} {{sfn|Roatsch Jaumann et al.|2009|p=765|loc=Tables 24.1–2}}
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| | surface_grav = {{Gr|0.6174|531.1|3}} [[Acceleration|m/s²]] {{efn|name=surface gravity}}
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| | escape_velocity = {{V2|0.6174|531.1|3}} km/s{{efn|name=escape velocity}}
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| | rotation = [[Synchronous rotation|synchronous]]{{sfn|Jaumann Clark et al.|2009|p=659}}
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| | axial_tilt = zero
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| | albedo =
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| {{plainlist |
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| * {{val|1.229|0.005}} ([[geometric albedo|geometric]]){{sfn|Verbiscer French et al.|2007}}
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| * {{val|0.80|0.15}} ([[bond albedo|bond]]){{sfn|Jaumann Clark et al.|2009|p=662|loc=Table 20.4}}
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| * {{val|0.67|0.11}} (bolometric bond){{sfn|Howett Spencer et al.|2010|p=581|loc=Table 7}}
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| }}
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| | magnitude = 10.2{{sfn|Observatorio ARVAL}}
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| | single_temperature = {{val|86|1|u=K}}{{sfn|Stone|Miner|1982}}
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| | note = no
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| }}
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| '''Tethys''' or '''Saturn III''' is a mid-sized [[natural satellite|moon]] of [[Saturn]] about {{convert|1060|km|mi|abbr=on}} across. It was discovered by [[Giovanni Domenico Cassini|G. D. Cassini]] in 1684 and is named after the titan [[Tethys (mythology)|Tethys]] of [[Greek mythology]].
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| Tethys has a low density of 0.98 g/cm³ indicating that it is made of water ice with just a small fraction of rock. This is confirmed by the spectroscopy of its surface, which identified water ice as the dominant surface material. A small amount of an unidentified dark material is present as well. The surface of Tethys is very bright, being second brightest among the moons of Saturn after [[Enceladus (moon)|Enceladus]], and neutral in color.
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| Tethys is heavily cratered and cut by a number of large scale faults/graben. The largest impact crater—[[Odysseus (crater)|Odysseus]] is about 400 km in diameter, while the largest graben—[[Ithaca Chasma]] is about 100 km wide and more than 2000 km long. These two largest surface features may be related. A small part of the surface is covered by smooth plains that may be cryovolcanic in origin. Like all other regular moons of Saturn Tethys formed from the Saturnian sub-nebula—a disk of gas and dust that surrounded Saturn soon after its formation.
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| Tethys has been approached by several space probes including [[Pioneer 11]] (1979), [[Voyager 1]] (1980), [[Voyager 2]] (1981), and multiple times by [[Cassini–Huygens|Cassini]] since 2004.
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| == Discovery and naming ==
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| Tethys was discovered by [[Giovanni Domenico Cassini]] in 1684 together with [[Dione (moon)|Dione]], another moon of Saturn. He had also discovered two moons, [[Rhea (moon)|Rhea]] and [[Iapetus (moon)|Iapetus]] earlier, in 1671–72.{{sfn|Van Helden|1994}} Cassini observed all of these moons using a large [[aerial telescope]] he set up on the grounds of the [[Paris Observatory]].{{sfn|Price|2000|p=279}}
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| Cassini named the four new moons as ''[[Sidera Lodoicea]]'' ("the stars of Louis") to honour king [[Louis XIV of France]].{{sfn|Cassini|1686–1692}} By the end of the seventeenth century, astronomers fell into the habit of referring to them and [[Titan (moon)|Titan]] as ''Saturn I'' through ''Saturn V'' (Tethys, Dione, Rhea, Titan, Iapetus).{{sfn|Van Helden|1994}} Once [[Mimas (moon)|Mimas]] and [[Enceladus (moon)|Enceladus]] were discovered in 1789, the numbering scheme was extended to ''Saturn VII'' by bumping the older five moons up two slots. The discovery of [[Hyperion (moon)|Hyperion]] in 1848 changed the numbers one last time, bumping Iapetus up to ''Saturn VIII''. Henceforth, the numbering scheme would remain fixed.
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| The modern names of all seven satellites of Saturn come from [[John Herschel]] (son of [[William Herschel]], discoverer of Mimas and Enceladus).{{sfn|Van Helden|1994}} In his 1847 publication ''Results of Astronomical Observations made at the Cape of Good Hope'',{{sfn|Lassell|1848}} he suggested the names of the [[Titan (mythology)|Titans]], sisters and brothers of [[Cronus|Kronos]] (the Greek analogue of Saturn), be used.
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| Tethys is named after the titan [[Tethys (mythology)|Tethys]] of [[Greek mythology]].{{sfn|Van Helden|1994}} It is also designated '''Saturn III''' or '''S III Tethys'''. The correct adjectival form of the moon's name is ''Tethyan'', although other forms are also used.
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| == Orbit ==
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| Tethys orbits Saturn at a distance of about 295000 km (about 4.4 Saturn's radii) from the center of the planet. The [[orbital eccentricity]] is negligible, while the [[orbital inclination]] is about 1 degree. The moon is locked in an inclination [[orbital resonance|resonance]] with [[Mimas (moon)|Mimas]], which, however, does not cause any noticeable orbital eccentricity and tidal heating.{{sfn|Matson Castillo-Rogez et al.|2009|pp=604–05}}
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| The Tethyan orbit lies deep inside the [[magnetosphere of Saturn]], so the plasma co-rotating with the planet strikes the trailing hemisphere of the moon. Tethys is also subject to constant bombardment by the energetic particles (electrons and ions) present in the magnetosphere.{{sfn|Khurana Russell et al.|2008|pp=466–67}}
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| Tethys has two [[co-orbital configuration|co-orbital moons]], [[Telesto (moon)|Telesto]] and [[Calypso (moon)|Calypso]] orbiting near Tethys's [[Trojan (astronomy)|Trojan]] points {{L4}} (60° ahead) and {{L5}} (60° behind).
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| == Physical characteristics ==
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| [[File:Map of Tethys PIA 14931 Jun 2012.jpg|thumb|left|300px|Tethys basemap (trailing hemisphere on the right)]]
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| At 1066 km in diameter, Tethys is the [[List of moons|16th largest moon]] in the [[Solar System]], and is more massive than all known moons smaller than itself combined.{{efn|name=moon masses}} The density of Tethys is 0.98 g/cm³, indicating that it is composed almost entirely of water-ice. The mass of rocky material can not exceed 6% of the mass of this moon.{{sfn|Thomas Burns et al.|2007}}
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| It is not known whether Tethys is differentiated into a rocky [[core (geology)|core]] and ice [[mantle (geology)|mantle]]. However, if it is differentiated, the radius of the core is about 145 km. Due to the action of tidal and rotational forces, Tethys has the shape of [[triaxial ellipsoid]]. The dimensions of this ellipsoid are consistent with this moon having a homogeneous interior.{{sfn|Thomas Burns et al.|2007}} The existence of a subsurface ocean—a layer of liquid water in the interior of Tethys — is considered unlikely.{{sfn|Hussmann Sohl et al.|2006}}
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| The surface of Tethys is one of the most reflective (at visual wavelengths) in the solar system, with a visual albedo of 1.229. This very high albedo is the result of the sandblasting of particles from Saturn's E-ring, a faint ring composed of small, water-ice particles generated by Enceladus's south polar geysers.{{sfn|Verbiscer French et al.|2007}} The radar albedo of the Tethyan surface is also very high.{{sfn|Ostro West et al.|2006}} The leading hemisphere of Tethys is brighter by 10–15% than the trailing one.{{sfn|Filacchione Capaccioni et al.|2007}}
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| The high albedo indicates that the surface of Tethys is composed of almost pure water ice with only a small amount of a dark material. The visible spectrum of the moon is flat and featureless, while in the [[near-infrared]] strong water ice absorption bands at 1.25, 1.5, 2.0 and 3.0 μm wavelengths are visible.{{sfn|Filacchione Capaccioni et al.|2007}} No compound other than crystalline water ice has been unambiguously identified on Tethys.{{sfn|Jaumann Clark et al.|2009|pp=651–654}} (Possible constituents include [[Organic compound|organics]], [[ammonia]] and [[carbon dioxide]].) The dark material in the ice has the same spectral properties as seen on the surfaces of the dark Saturnian moons—Iapetus and Hyperion. The most probable candidate is [[nanophase]] iron or [[hematite]].{{sfn|Jaumann Clark et al.|2009|pp=654–656}} Measurements of the [[thermal emission]] as well as radar observations by the Cassini spacecraft show that the icy [[regolith]] on the surface of Tethys is structurally complex{{sfn|Ostro West et al.|2006}} and has a large [[porosity]] exceeding 95%.{{sfn|Carvano Migliorini et al.|2007}}
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| == Surface features ==
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| [[File:Color map of Tethys.jpg|thumb|Enhanced-color map of Tethys showing the reddening of the trailing hemisphere (left) and the bluish band on the leading hemisphere (right)]]
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| {{main|List of geological features on Tethys}}
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| === Color patterns ===
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| The surface of Tethys has a number of large-scale features distinguished by their color and sometimes brightness. The trailing hemisphere gets increasingly red and dark as the anti-apex of motion is approached. This darkening is responsible for the hemispheric albedo asymmetry mentioned above.{{sfn|Schenk Hamilton et al.|2011|pp=740–44}} The leading hemisphere also reddens slightly as the [[wiktionary:apex|apex]] of the motion is approached, although without any noticeable darkening.{{sfn|Schenk Hamilton et al.|2011|pp=740–44}} Such a bifurcated color pattern results in the existence of a bluish band between hemispheres following a great circle that runs through the poles. This coloration and darkening of the Tethyan surface is typical for Saturnian middle-sized satellites. Its origin may be related to a deposition of bright ice particles from the [[Rings_of_Saturn#E_Ring|E-ring]] onto the leading hemispheres and dark particles coming from outer satellites on the trailing hemispheres. The darkening of the trailing hemispheres can also be caused by the impact of plasma from the [[magnetosphere of Saturn]], which co-rotates with the planet.{{sfn|Schenk Hamilton et al.|2011|pp=750–53}}
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| On the leading hemisphere of Tethys spacecraft observations have found a dark bluish band spanning 20° to the south and north from the equator. The band has an elliptical shape getting narrower as it approaches the trailing hemisphere. A comparable band exists only on Mimas.{{sfn|Schenk Hamilton et al.|2011|pp=745–46}} The band is almost certainly caused by the influence of energetic electrons from the Saturnian magnetosphere with energies greater than about 1 [[MeV]]. These particles drift in the direction opposite to the rotation of the planet and preferentially impact areas on the leading hemisphere close to the equator.{{sfn|Schenk Hamilton et al.|2011|pp=751–53}} Temperature maps of Tethys obtained by ''Cassini'', have shown this bluish region is cooler at midday than surrounding areas, giving the satellite a "Pac-man"-like appearance at mid-infrared wavelengths.<ref>{{cite web | url = http://saturn.jpl.nasa.gov/news/cassinifeatures/feature20121126/ | title = Cassini Finds a Video Gamers' Paradise at Saturn|date=2012-11-26|accessdate=2012-11-26|publisher=NASA }}</ref>
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| === Geology ===
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| The geology of Tethys is relatively simple. It surface is mostly made of hilly cratered terrain dominated by craters more than 40 km in diameter. A smaller part of the surface is represented by the smooth plains on the trailing hemisphere. There are also a number of tectonic features such as [[chasmata]] and [[trough (geology)|trough]]s.{{sfn|Moore Schenk et al.|2004|pp=424–30}}
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| [[File:PIA07738 Tethys mosaic contrast-enhanced.jpg|thumb|left|''[[Cassini–Huygens|Cassini]]'' view of Tethys's Saturn-facing hemisphere, showing the giant [[rift]] [[Ithaca Chasma]], crater Telemachus at top, and smooth plains at right]]
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| The western part of the leading hemisphere of Tethys is dominated by a large impact crater called [[Odysseus (crater)|Odysseus]], whose 450 km diameter is nearly 2/5 of that of Tethys itself. The crater is now quite flat or more precisely, its floor conforms to Tethys's spherical shape. This is most likely due to the viscous relaxation of the Tethyan icy crust over geologic time. Nevertheless the [[rim (craters)|rim]] crest of Odysseus is elevated by approximately 5 km above the mean satellite radius. The central complex of Odysseus features a central pit 2–4 km deep surrounded by massifs elevated by 6–9 km above the crater floor, which itself is about 3 km below the average radius.{{sfn|Moore Schenk et al.|2004|pp=424–30}}
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| The second major feature seen on Tethys is a huge valley called [[Ithaca Chasma]], about 100 km wide and 3 km deep. It is more than 2000 km in length, approximately 3/4 of the way around Tethys's circumference.{{sfn|Moore Schenk et al.|2004|pp=424–30}} Ithaca Chasma occupies about 10% of the surface of Tethys. It is approximately concentric with Odysseus—a pole of Ithaca Chasma lies only approximately 20° from the crater.{{sfn|Jaumann Clark et al.|2009|pp=645–46, 669}}
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| It is thought that Ithaca Chasma formed as Tethys's internal liquid water solidified, causing the moon to expand and cracking the surface to accommodate the extra volume within. The subsurface ocean may have resulted from a 2:3 [[orbital resonance]] between Dione and Tethys early in the solar system's history that led to [[orbital eccentricity]] and [[Tidal acceleration#Tidal heating|tidal heating]] of Tethys's interior. The ocean would have frozen after the moons escaped from the resonance.{{sfn|Chen|Nimmo|2008}} There is another theory about the formation of Ithaca Chasma: when the impact that caused the great crater Odysseus occurred, the shock wave traveled through Tethys and fractured the icy, brittle surface. In this case Ithaca Chasma would be the outmost ring graben of Odysseus.{{sfn|Moore Schenk et al.|2004|pp=424–30}} However, age determination based on crater counts in high-resolution Cassini images showed that Ithaca Chasma is older than Odysseus making the impact hypothesis unlikely.{{sfn|Jaumann Clark et al.|2009|pp=645–46, 669}}
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| [[File:Tethys near true.jpg|thumb|Huge, shallow [[Complex crater|crater]] [[Odysseus (crater)|Odysseus]], with its uplifted central complex, the Scheria Montes, is at the top of this image.]]
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| The smooth plains on the trailing hemisphere are approximately antipodal to Odysseus, although they extend about 60° to the northeast from the exact antipode. The plains have a relatively sharp boundary with the surrounding cratered terrain. The location of this unit near Odysseus' antipode argues for a connection between the crater and plains. The latter can be a result of focusing the [[seismic wave]]s produced by the impact in the center of the opposite hemisphere. However the smooth appearance of the plains together with their sharp boundaries (impact shaking would have produced a wide transitional zone) indicates that they formed by endogenic intrusion, possibly along the lines of weakness in the Tethyan lithosphere created by Odysseus impact.{{sfn|Moore Schenk et al.|2004|pp=424–30}}{{sfn|Jaumann Clark et al.|2009|pp=650–51}}
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| {{See also|List of quadrangles on Tethys}}
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| === Impact craters and chronology ===
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| The majority of Tethyan impact craters are of a simple central peak type. Those more than 150 km in diameter show more complex peak ring morphology. Only Odysseus crater has a central depression resembling a central pit. Older impact craters are somewhat shallower than young ones implying a degree of relaxation.{{sfn|Jaumann Clark et al.|2009|p=642}}
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| The density of impact craters varies across the surface of Tethys. The higher the crater density, the older the surface. This allows scientists to establish a relative chronology for Tethys. The cratered terrain is the oldest unit likely dating back to the [[Formation and evolution of the Solar System|Solar System formation]] 4.56 billion years ago.{{sfn|Dones Chapman et al.|2009|pp=626–30}} The youngest unit lies within Odysseus crater with an estimated age from 3.76 to 1.06 billion years, depending on the absolute chronology used.{{sfn|Dones Chapman et al.|2009|pp=626–30}} The age of Ithaca Chasma is intermediate between the two ages mentioned above.{{sfn|Giese Wagner et al.|2007}}
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| == Origin and evolution ==
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| Tethys is thought to have formed from an [[accretion disc]] or subnebula; a disc of gas and dust that either existed around Saturn for some time after its formation.{{sfn|Johnson|Estrada|2009|pp=59–60}} The low temperature at the position of Saturn in the Solar nebular means that water ice was the primary solid from which all moons formed. Other more volatile compounds like [[ammonia]] and [[carbon dioxide]] were likely present as well, though their abundances are not well constrained.{{sfn|Matson Castillo-Rogez et al.|2009|pp=582–83}}
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| The extremely water-ice-rich composition of Tethys remains unexplained. The conditions in the Saturnian sub-nebula likely favored conversion of the molecular [[nitrogen]] and [[carbon monoxide]] into ammonia and [[methane]], respectively.{{sfn|Johnson|Estrada|2009|pp=65–68}} This can partially explain why Saturnian moons including Tethys contain more water ice than outer Solar System bodies like [[Pluto]] or [[Triton (moon)|Triton]] as the oxygen freed from carbon monoxide would react with the hydrogen forming water.{{sfn|Johnson|Estrada|2009|pp=65–68}} One of the most interesting explanations proposed is that the rings and inner moons accreted from the tidally stripped ice-rich crust of a Titan-like moon before it was swallowed by Saturn.{{sfn|Canup|2010}}
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| The accretion process probably lasted for several thousand years before the moon was fully formed. Models suggest that impacts accompanying accretion caused heating of Tethys's outer layer, reaching a maximum temperature of around 155 K at a depth of about 29 km.{{sfn|Squyres Reynolds et al.|1988|p=8788|loc=Table 2}} After the end of formation due to [[thermal conduction]], the subsurface layer cooled, while the interior heated up.{{sfn|Squyres Reynolds et al.|1988|pp=8791–92}} The cooling near-surface layer contracted, while the interior expanded. This caused strong [[Stress (mechanics)|extensional stresses]] in the moon's crust reaching estimates of 5.7 [[Pascal (unit)|MPa]], which likely led to cracking.{{sfn|Hillier|Squyres|1991}}
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| Since Tethys lacks substantial rock content, the heating by decay of radioactive elements is unlikely to have played a significant role in further evolution of this moon.{{sfn|Matson Castillo-Rogez et al.|2009|p=590}} This also means that Tethys may have never experienced any significant melting unless its interior was heated by tides. They may have occurred, for instance, during the passage of Tethys through an orbital resonance with Dione or some other moon.{{sfn|Matson Castillo-Rogez et al.|2009|pp=604–05}} Still, present knowledge of the evolution of Tethys is very limited.
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| == Exploration ==
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| [[File:Tethys.gif|thumb| Animation of Tethys's rotation]]
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| [[Pioneer 11]] flew by Saturn in 1979, and its closest approach to Tethys was 329,197 km on September 1, 1979.{{sfn|Muller, Pioneer 11 Full Mission Timeline}}
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| One year later, on 12 November 1980, Voyager 1 flew at the minimal distance of 415,670 km from Tethys.{{sfn|Stone|Miner|1981}} Its twin spacecraft, Voyager 2, passed as close as 93,000 km{{sfn|Stone|Miner|1981}} from the moon on 1 September 1981.{{sfn|Stone|Miner|1982}} While both spacecraft took images of Tethys, the resolution of Voyager's 1 images did not exceed 15 km, and only those obtained by Voyager 2 had a resolution as high as 2 km.{{sfn|Stone|Miner|1982}} The first geological feature discovered in 1980 by Voyager 1 was Ithaca Chasma.{{sfn|Stone|Miner|1981}} Later in 1981 Voyager 2 revealed that it almost circled the moon running for 270°. Voyager 2 also discovered the Odysseus crater.{{sfn|Stone|Miner|1982}} Tethys was the best imaged Saturnian satellite by the Voyagers.{{sfn|Moore Schenk et al.|2004|pp=424–30}}
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| The ''[[Cassini-Huygens|Cassini]]'' spacecraft entered orbit around Saturn in 2004. During its primary mission from June 2004 through June 2008 it performed one very close targeted flyby of Tethys on September 24, 2005 at the distance of 1503 km. In addition to this flyby the spacecraft performed seven non-targeted flybys during its primary and equinox missions in 2004–2010 at distances of tens of thousands of kilometers.{{sfn|Jaumann Clark et al.|2009|pp=639–40|loc=Table 20.2 at p. 641}}{{sfn|Seal|Buffington|2009|pp=725–26}}
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| Another flyby of Tethys took place on August 14, 2010 (during the solstice mission) at a distance of 38300 km, when the fourth-largest crater on Tethys, [[Penelope (crater)|Penelope]], which is 207 km wide, was imaged.{{sfn|Cook|2010}} More non-targeted flybys are planned for the solstice mission in 2011–2017.{{sfn|Cassini Solstice Mission}}
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| Cassini's observations allowed high-resolution maps of Tethys to be produced with the resolution of 0.29 km.{{sfn|Roatsch Jaumann et al.|2009|p=768}} The spacecraft obtained spatially resolved near-infrared spectra of Tethys showing that its surface is made of water ice mixed with a dark material,{{sfn|Filacchione Capaccioni et al.|2007}} while the far-infrared observations constrained the bolometric [[bond albedo]].{{sfn|Howett Spencer et al.|2010|p=581|loc=Table 7}} The radar observations at the wavelength of 2.2 cm showed that the ice regolith has a complex structure and is very porous.{{sfn|Ostro West et al.|2006}} The observations of plasma in the vicinity of Tethys demonstrated that it is a geologically dead body producing no new plasma in the Saturnian magnetosphere.{{sfn|Khurana Russell et al.|2008|pp=472–73}}
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| Future missions to Tethys and the Saturn system are uncertain, but one possibility is the [[Titan Saturn System Mission]].
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| == Tethys in fiction ==
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| {{further|Saturn's moons in fiction}}
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| == See also ==
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| * [[17 Thetis]]
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| == Notes ==
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| {{notes
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| | notes =
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| {{efn
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| | name = surface gravity
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| | Surface gravity derived from the mass ''m'', the [[gravitational constant]] ''G'' and the radius ''r'' : <math>Gm/r^2</math>.
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| }}
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| {{efn
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| | name = escape velocity
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| | Escape velocity derived from the mass ''m'', the gravitational constant ''G'' and the radius ''r'' : {{math|{{radical|2''Gm''/''r''}}}}.
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| }}
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| {{efn
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| | name = dict-def
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| | {{respell|TEE|thəs}} or {{respell|TETH|əs}}
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| }}
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| {{efn
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| | name = moon masses
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| | The masses of smaller spherical moons are (in kg): [[Enceladus (moon)|Enceladus]]—1.1{{e|20}}, [[Miranda (moon)|Miranda]]—0.6{{e|20}}, [[Proteus (moon)|Proteus]]—0.5{{e|20}}, [[Mimas (moon)|Mimas]]—0.4{{e|20}}. The total mass of remaining moons is about 0.9{{e|20}}. So, the total mass of all moons smaller than Tethys is about 3.5{{e|20}}. (See [[List of moons by diameter]])
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| }}
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| }}
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| == Citations ==
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| {{reflist
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| | colwidth = 30em
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| | refs =
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| <ref name="NASACelestia">
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| [http://exp.arc.nasa.gov/downloads/celestia/data/solarsys.ssc NASA Celestia]
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| {{dead link|date=December 2011}}
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| </ref> | |
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| }}
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| == References ==
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| {{refbegin|30em}}
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| * {{cite doi | 10.1038/nature09661 }}
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| * {{cite doi | 10.1016/j.icarus.2006.09.008 }}
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| * {{cite doi | 10.1098/rstl.1686.0013 }}<!-- This journal became the Philosophical Transactions of the Royal Society of London in 1775. Are there any earlier publications? Two years seems a long time... -->
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| * {{cite web
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| | title = Cassini Solstice Mission: Saturn Tour Dates: 2011
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| | publisher = JPL/NASA
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| | url = http://saturn.jpl.nasa.gov/mission/saturntourdates/saturntourdates2011/
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| | accessdate = 2011-12-18
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| | ref = {{sfnRef|Cassini Solstice Mission}}
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| }}
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| * {{cite conference
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| | last1 = Chen
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| | first1 = E. M. A.
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| {{refend}}
| |
| | |
| == External links ==
| |
| | |
| {{Spoken Wikipedia|Tethys (moon).ogg|2010-01-14}}
| |
| {{commons category|Tethys}}
| |
| * [http://solarsystem.nasa.gov/planets/profile.cfm?Object=Sat_Tethys Tethys Profile] at [http://solarsystem.nasa.gov NASA's Solar System Exploration Site]
| |
| * [http://www.solarviews.com/cap/sat/vtethys1.htm Movie of Tethys's rotation by Calvin J. Hamilton (based on Voyager images)]
| |
| * [http://www.planetary.org/explore/topics/saturn/tethys.html The Planetary Society: Tethys]
| |
| * [http://ciclops.org/search.php?x=20&y=7&search=Tethys Cassini images of Tethys]
| |
| * [http://photojournal.jpl.nasa.gov/target/Tethys Images of Tethys at JPL's Planetary Photojournal]
| |
| * Movie of [http://sos.noaa.gov/videos/Tethys.mov Tethys' rotation] from the National Oceanic and Atmospheric Administration
| |
| * Tethys [http://www.ciclops.org/view/6533/Map_of_Tethys_-_August_2010 global] and [http://www.ciclops.org/view/6534/Tethys_Polar_Maps_-_August_2010 polar] basemaps (August 2010) from Cassini images
| |
| * [http://ciclops.org/view.php?id=5074 Tethys atlas (August 2008) from Cassini images]
| |
| * [http://planetarynames.wr.usgs.gov/Page/TETHYS/target Tethys nomenclature] and [http://planetarynames.wr.usgs.gov/images/tethys_comp.pdf Tethys map with feature names] from the [http://planetarynames.wr.usgs.gov USGS planetary nomenclature page]
| |
| | |
| {{Moons of Saturn|state=uncollapsed}}
| |
| {{Solar System moons (compact)}}
| |
| | |
| {{DEFAULTSORT:Tethys (Moon)}}
| |
| [[Category:Moons of Saturn]]
| |
| [[Category:Astronomical objects discovered in 1684]]
| |
| [[Category:Planemos]]
| |
| [[Category:Tethys (moon)| ]]
| |