Lakes of Titan

False-color, medium-resolution Cassini synthetic aperture radar mosaic of Titan's north polar region, showing hydrocarbon seas, lakes and tributary networks. Blue coloring indicates low radar reflectivity areas, caused by bodies of liquid ethane, methane and dissolved nitrogen.[1] Kraken Mare, the largest sea on Titan, is at lower left. Ligeia Mare is the large body below the pole, and Punga Mare at half its size is just left of the pole. White areas have not been imaged.

The lakes of Titan, Saturn's largest moon, are bodies of liquid ethane and methane that have been detected by the Cassini–Huygens space probe, and had been suspected long before.[2] The large ones are known as maria (seas) and the small ones as lacūs (lakes).[3]

History

Titan lakes (September 11, 2017)
Size comparison of Ligeia Mare with Lake Superior.
Radargram acquired by the Cassini RADAR altimeter showing the surface and seafloor of Ligeia Mare along the transect highlined by the red line. In each column is shown the received power as function of time.
Vid Flumina,[4] a 400 km long river emptying into Ligeia Mare (in lower right corner of top image).

The possibility that there were seas on Titan was first suggested based on data from the Voyager 1 and 2 space probes, launched in August and September 1977. The data showed Titan to have a thick atmosphere of approximately the correct temperature and composition to support them. Direct evidence was not obtained until 1995 when data from the Hubble Space Telescope and other observations had already suggested the existence of liquid methane on Titan, either in disconnected pockets or on the scale of satellite-wide oceans, similar to water on Earth.[5]

The Cassini mission affirmed the former hypothesis, although not immediately. When the probe arrived in the Saturnian system in 2004, it was hoped that hydrocarbon lakes or oceans might be detectable by reflected sunlight from the surface of any liquid bodies, but no specular reflections were initially observed.[6]

The possibility remained that liquid ethane and methane might be found on Titan's polar regions, where they were expected to be abundant and stable.[7] In Titan's south polar region, an enigmatic dark feature named Ontario Lacus was the first suspected lake identified, possibly created by clouds that are observed to cluster in the area.[8] A possible shoreline was also identified near the pole via radar imagery.[9] Following a flyby on July 22, 2006, in which the Cassini spacecraft's radar imaged the northern latitudes (which were at the time in winter), a number of large, smooth (and thus dark to radar) patches were seen dotting the surface near the pole.[10] Based on the observations, scientists announced "definitive evidence of lakes filled with methane on Saturn's moon Titan" in January 2007.[7][11] The Cassini–Huygens team concluded that the imaged features are almost certainly the long-sought hydrocarbon lakes, the first stable bodies of surface liquid found off Earth. Some appear to have channels associated with liquid and lie in topographical depressions.[7] Channels in some regions have created surprisingly little erosion, suggesting erosion on Titan is extremely slow, or some other recent phenomena may have wiped out older riverbeds and landforms.[12] Overall, the Cassini radar observations have shown that lakes cover only a few percent of the surface and are concentrated near the poles, making Titan much drier than Earth.[13] The high relative humidity of methane in Titan's lower atmosphere could be maintained by evaporation from lakes covering only 0.002–0.02% of the whole surface.[14]

During a Cassini flyby in late February 2007, radar and camera observations revealed several large features in the north polar region interpreted as large expanses of liquid methane and/or ethane, including one, Ligeia Mare, with an area of 126,000 km2 (48,649 sq. mi.) ( (slightly larger than Lake Michigan–Huron, the largest freshwater lake on Earth), and another, Kraken Mare, that would later prove to be three times that size. A flyby of Titan's southern polar regions in October 2007 revealed similar, though far smaller, lakelike features.[15]

Infrared specular reflection off Jingpo Lacus, a north polar body of liquid.
Image of Titan taken during Huygens' descent, showing hills and topographical features that resemble a shoreline and drainage channels.

During a close Cassini flyby in December 2007 the visual and mapping instrument observed a lake, Ontario Lacus, in Titan's south polar region. This instrument identifies chemically different materials based on the way they absorb and reflect infrared light. Radar measurements made in July 2009 and January 2010 indicate that Ontario Lacus is extremely shallow, with an average depth of 0.4–3.2 m (1'4"-10.5'), and a maximum depth of 2.9–7.4 m (9.5'-24'4").[16] It may thus resemble a terrestrial mudflat. In contrast, the northern hemisphere's Ligeia Mare has depths of 170 m (557'9").[17]

Chemical composition and surface roughness of the lakes

According to Cassini data, scientists announced on February 13, 2008, that Titan hosts within its polar lakes "hundreds of times more natural gas and other liquid hydrocarbons than all the known oil and natural gas reserves on Earth." The desert sand dunes along the equator, while devoid of open liquid, nonetheless hold more organics than all of Earth's coal reserves.[18] It has been estimated that the visible lakes and seas of Titan contain about 300 times the volume of Earth's proven oil reserves.[19] In June 2008, Cassini's Visible and Infrared Mapping Spectrometer confirmed the presence of liquid ethane beyond doubt in a lake in Titan's southern hemisphere.[20] The exact blend of hydrocarbons in the lakes is unknown. According to a computer model, 3/4 of an average polar lake is ethane, with 10 percent methane, 7 percent propane and smaller amounts of hydrogen cyanide, butane, nitrogen and argon.[21] Benzene is expected to fall like snow and quickly dissolve into the lakes, although the lakes may become saturated just as the Dead Sea on Earth is packed with salt. The excess benzene would then build up in a mud-like sludge on the shores and on the lake floors before eventually being eroded by ethane rain, forming a complex cave-riddled landscape.[22]Salt-like compounds composed of ammonia and acetylene are also predicted to form[23]. However, the chemical composition and physical properties of the lakes probably varies from one lake to another (Cassini observations in 2013 indicate Ligeia Mare is filled with a ternary mixture of methane, ethane, and nitrogen and consequently the probe's radar signals were able to detect the sea floor 170 m (557'9") below the liquid surface).[24]

No waves were initially detected by Cassini as the northern lakes emerged from winter darkness (calculations indicate wind speeds of less than 1 meter per second (2.2 MPH) should whip up detectable waves in Titan's ethane lakes but none were observed). This may be either due to low seasonal winds or solidification of hydrocarbons. The optical properties of solid methane surface (close to the melting point) are quite close to the properties of liquid surface however the viscosity of solid methane, even near the melting point, is many orders of magnitude higher, which might explain extraordinary smoothness of the surface.[25] Solid methane is denser than liquid methane so it will eventually sink. It is possible that the methane ice could float for a time as it probably contains bubbles of nitrogen gas from Titan's atmosphere.[26] Temperatures close to the freezing point of methane (90.4 Kelvins/-296.95 F) could lead to both floating and sinking ice - that is, a hydrocarbon ice crust above the liquid and blocks of hydrocarbon ice on the bottom of the lake bed. The ice is predicted to rise to the surface again at the onset of spring before melting. Since 2014, Cassini has detected transient features in scattered patches in Kraken Mare, Ligeia Mare and Punga Mare. Laboratory experiments suggest these features might be vast patches of bubbles caused by the rapid release of nitrogen dissolved in the lakes. This phenomenon is predicted to occur as the lakes warm or whenever methane-rich fluids mix with ethane-rich ones due to heavy rainfall.[27] An alternative explanation is the transient features may be shallow capillary waves (ripples) moving at about 0.7 meters per second (1.5 MPH) and at heights of about 1.5 centimeters (1/2").[28]

Cyclones driven by evaporation and involving rain as well as gale-force winds of up 20 meters per second (72 km/h [45 MPH]) are expected to form over the large northern seas only (Kraken Mare, Ligeia Mare, Punga Mare) in northern summer during 2017, lasting up to ten days.[29]. However, a 2017 analysis of Cassini data from 2007-15 indicates waves across these three seas were diminutive, reaching only about 1 centimeter (25/64") high and 20 centimeters (8") long. The results call into question the early summer’s classification as the beginning of the Titan’s windy season, because high winds probably would have made for larger waves. [30]

Observation of specular reflections

Near-infrared radiation from the Sun reflecting off Titan's hydrocarbon seas.

On 21 December 2008, Cassini passed directly over Ontario Lacus at an altitude of 1900 km (1,180 mi) and was able to observe specular reflection in radar observations. The signals were much stronger than anticipated and saturated the probe's receiver. The conclusion drawn from the strength of the reflection was that the lake level did not vary by more than 3 mm (1/8") over a first Fresnel zone reflecting area only 100 m (328') wide (smoother than any natural dry surface on Earth). From this it was surmised that surface winds in the area are minimal at that season and/or the lake fluid is more viscous than expected.[31][32]

On 8 July 2009, Cassini's Visual and Infrared Mapping Spectrometer (VIMS) observed a specular reflection in 5 µm infrared light off a northern hemisphere body of liquid at 71° N, 337° W. This has been described as at the southern shoreline of Kraken Mare,[33] but on a combined radar-VIMS image the location is shown as a separate lake (later named Jingpo Lacus). The observation was made shortly after the north polar region emerged from 15 years of winter darkness. Because of the polar location of the reflecting liquid body, the observation required a phase angle close to 180°.[34]

Equatorial in-situ observations by the Huygens probe

The discoveries in the polar regions contrast with the findings of the Huygens probe, which landed near Titan's equator on January 14, 2005. The images taken by the probe during its descent showed no open areas of liquid, but strongly indicated the presence of liquids in the recent past, showing pale hills crisscrossed with dark drainage channels that lead into a wide, flat, darker region. It was initially thought that the dark region might be a lake of a fluid or at least tar-like substance, but it is now clear that Huygens landed on the dark region, and that it is solid without any indication of liquids. A penetrometer studied the composition of the surface as the craft impacted it, and it was initially reported that the surface was similar to wet clay, or perhaps crème brûlée (that is, a hard crust covering a sticky material). Subsequent analysis of the data suggests that this reading was likely caused by Huygens displacing a large pebble as it landed, and that the surface is better described as a "sand" made of ice grains.[35] The images taken after the probe's landing show a flat plain covered in pebbles. The pebbles may be made of water ice and are somewhat rounded, which may indicate the action of fluids.[36] Thermometers indicated that heat was wicked away from Huygens so quickly that the ground must have been damp, and one image shows light reflected by a dewdrop as it falls across the camera's field of view. On Titan, the feeble sunlight allows only about one centimeter of evaporation per year (versus one meter of water on Earth), but the atmosphere can hold the equivalent of about 10 meters (28') of liquid before rain forms (versus about 2 cm [25/32"] on Earth). So Titan's weather is expected to feature downpours of several meters (15-20') causing flash floods, interspersed by decades or centuries of drought (whereas typical weather on Earth includes a little rain most weeks).[37] Cassini has observed equatorial rainstorms only once since 2004. Despite this, a number of long-standing tropical hydrocarbon lakes were unexpectedly discovered in 2012 [38] (including one near the Huygens landing site in the Shangri-La region which is about half the size of Utah's Great Salt Lake, with a depth of at least 1 meter [3'4"]). As on Earth, the likely supplier is probably underground aquifers, in other words the arid equatorial regions of Titan contain "oases".[39]

Impact of Titan's methane cycle and geology on lake formation

Evolving feature in Ligeia Mare

Models of oscillations in Titan's atmospheric circulation suggest that over the course of a Saturnian year, liquid is transported from the equatorial region to the poles, where it falls as rain. This might account for the equatorial region's relative dryness.[40] According to a computer model, intense rainstorms should occur in normally rainless equatorial areas during Titan's vernal and autumnal equinoxes—enough liquid to carve out the type of channels that Huygens found.[41] The model also predicts energy from the Sun will evaporate liquid methane from Titan's surface except at the poles, where the relative absence of sunlight makes it easier for liquid methane to accumulate into permanent lakes. The model also apparently explains why there are more lakes in the northern hemisphere. Due to the eccentricity of Saturn's orbit, the northern summer is longer than the southern summer and consequently the rainy season is longer in the north.

However, recent Cassini observations (from 2013) suggest geology may also explain the geographic distribution of the lakes and other surface features. One puzzling feature of Titan is the lack of impact craters at the poles and mid-latitudes, particularly at lower elevations. These areas may be wetlands fed by subsurface ethane and methane springs.[42] Any crater created by meteorites is thus quickly subsumed by wet sediment. The presence of underground aquifers could explain another mystery. Titan's atmosphere is full of methane, which according to calculations should react with ultraviolet radiation from the sun to produce liquid ethane. Over time, the moon should have built up an ethane ocean hundreds of meters (1,500'-2,500') deep instead of only a handful of polar lakes. The presence of wetlands would suggest that the ethane soaks into the ground, forming a subsurface liquid layer akin to groundwater on Earth. A possibility is that the formation of materials called clathrates changes the chemical composition of the rainfall runoff that charges the subsurface hydrocarbon "aquifers." This process leads to the formation of reservoirs of propane and ethane that may feed into some rivers and lakes. The chemical transformations taking place underground would affect Titan's surface. Lakes and rivers fed by springs from propane or ethane subsurface reservoirs would show the same kind of composition, whereas those fed by rainfall would be different and contain a significant fraction of methane.[43]

All but 3% of Titan's lakes have been found within a bright unit of terrain covering about 900 kilometers by 1,800 kilometers (559 x 1,118 mi.) near the north pole. The lakes found here have very distinctive shapes—rounded complex silhouettes and steep sides—suggesting deformation of the crust created fissures that could be filled up with liquid. A variety of formation mechanisms have been proposed. The explanations range from the collapse of land after a cryovolcanic eruption to karst terrain, where liquids dissolve soluble ice.[44]

Titan Mare Explorer

Titan Mare Explorer (TiME) was a proposed NASA/ESA lander that would splash down on Ligeia Mare and analyze its surface, shoreline and Titan's atmosphere.[45] However, it was turned down in August 2012, when NASA instead selected the InSight mission to Mars.[46]

Named lakes and seas

False-color near infrared view of Titan's northern hemisphere, showing its seas and lakes. Orange areas near some of them may be deposits of organic evaporite left behind by receding liquid hydrocarbon.
Intricate networks of channels drain into Kraken Mare (lower left) and Ligeia Mare (upper right).
Hydrocarbon lakes on Titan: Cassini radar image, 2006. Bolsena Lacus is at lower right, with Sotonera Lacus just above and to its left. Koitere Lacus and Neagh Lacus are in the middle distance, left of center and on the right margin, respectively. Mackay Lacus is at upper left.
Titan's "kissing lakes", formally named Abaya Lacus, about 65 km (40 mi) across
Feia Lacus, about 47 km (29 mi) across, a lake with several large peninsulas

Features labeled lacus are believed to be ethane/methane lakes, while features labeled lacuna are believed to be dry lake beds. Both are named after lakes on Earth.[3] Features labeled sinus are bays within the lakes or seas. They are named after bays and fjords on Earth. Features labeled insula are islands within the body of liquid. They are named after mythical islands. Titanean maria (large hydrocarbon seas) are named after sea monsters in world mythology.[3]

Sea names of Titan

NameCoordinatesLength (km)[note 1]Area (km2)Source of name
Kraken Mare68°00′N 310°00′W / 68.0°N 310.0°W / 68.0; -310.01,170ca. 400,000The Kraken, Norse sea monster.
Ligeia Mare79°00′N 248°00′W / 79.0°N 248.0°W / 79.0; -248.0500126,000Ligeia, one of the Sirens, Greek monsters
Punga Mare85°06′N 339°42′W / 85.1°N 339.7°W / 85.1; -339.7380Punga, Māori ancestor of sharks and lizards

Lake names of Titan

NameCoordinatesLength (km)[note 1]Source of name
Abaya Lacus73°10′N 45°33′W / 73.17°N 45.55°W / 73.17; -45.5565Lake Abaya, Ethiopia
Albano Lacus65°54′N 236°24′W / 65.9°N 236.4°W / 65.9; -236.46.2Lake Albano, Italy
Atitlán Lacus69°18′N 238°48′W / 69.3°N 238.8°W / 69.3; -238.813.7Lake Atitlán, Guatemala
Bolsena Lacus75°45′N 10°17′W / 75.75°N 10.28°W / 75.75; -10.28101Lake Bolsena, Italy
Cardiel Lacus70°12′N 206°30′W / 70.2°N 206.5°W / 70.2; -206.522Cardiel Lake, Argentina
Cayuga Lacus69°48′N 230°00′W / 69.8°N 230.0°W / 69.8; -230.022.7Cayuga Lake, USA
Crveno Lacus79°36′S 184°54′W / 79.6°S 184.9°W / -79.6; -184.941.0Crveno Jezero, Croatia
Feia Lacus73°42′N 64°25′W / 73.7°N 64.41°W / 73.7; -64.4147Lake Feia, Brazil
Freeman Lacus73°36′N 211°06′W / 73.6°N 211.1°W / 73.6; -211.126Lake Freeman, USA
Hammar Lacus48°36′N 308°17′W / 48.6°N 308.29°W / 48.6; -308.29200Lake Hammar, Iraq
Jingpo Lacus73°00′N 336°00′W / 73.0°N 336.0°W / 73.0; -336.0240Jingpo Lake, China
Junín Lacus66°54′N 236°54′W / 66.9°N 236.9°W / 66.9; -236.96.3Lake Junín, Peru
Kayangan Lacus86°18′S 236°54′W / 86.3°S 236.9°W / -86.3; -236.96.2Kayangan Lake, Philippines
Kivu Lacus87°00′N 121°00′W / 87.0°N 121.0°W / 87.0; -121.077.5Lake Kivu, on the border of Rwanda and the Democratic Republic of the Congo
Koitere Lacus79°24′N 36°08′W / 79.4°N 36.14°W / 79.4; -36.1468Koitere, Finland
Ladoga Lacus74°48′N 26°06′W / 74.8°N 26.1°W / 74.8; -26.1110Lake Ladoga, Russia
Lanao Lacus71°00′N 217°42′W / 71.0°N 217.7°W / 71.0; -217.734.5Lake Lanao, Philippines
Logtak Lacus70°48′N 124°06′W / 70.8°N 124.1°W / 70.8; -124.114.3Loktak Lake, India
Mackay Lacus78°19′N 97°32′W / 78.32°N 97.53°W / 78.32; -97.53180Lake Mackay, Australia
Müggel Lacus84°26′N 203°30′W / 84.44°N 203.5°W / 84.44; -203.5170Müggelsee, Germany
Mývatn Lacus78°11′N 135°17′W / 78.19°N 135.28°W / 78.19; -135.2855Mývatn, Iceland
Neagh Lacus81°07′N 32°10′W / 81.11°N 32.16°W / 81.11; -32.1698Lough Neagh, Northern Ireland
Ohrid Lacus71°48′N 221°54′W / 71.8°N 221.9°W / 71.8; -221.917.3Lake Ohrid, on the border of Republic of Macedonia and Albania
Oneida Lacus76°08′N 131°50′W / 76.14°N 131.83°W / 76.14; -131.8351Oneida Lake, United States
Ontario Lacus72°00′S 183°00′W / 72.0°S 183.0°W / -72.0; -183.0235Lake Ontario, on the border between Canada and the United States.
Sevan Lacus69°42′N 125°36′W / 69.7°N 125.6°W / 69.7; -125.646.9Lake Sevan, Armenia
Shoji Lacus79°42′S 166°24′W / 79.7°S 166.4°W / -79.7; -166.45.8Lake Shoji, Japan
Sionascaig Lacus41°31′S 278°07′W / 41.52°S 278.12°W / -41.52; -278.12143.2Loch Sionascaig, Scotland
Sotonera Lacus76°45′N 17°29′W / 76.75°N 17.49°W / 76.75; -17.4963Lake Sotonera, Spain
Sparrow Lacus84°18′N 64°42′W / 84.3°N 64.7°W / 84.3; -64.781.4Sparrow Lake, Canada
Towada Lacus71°24′N 244°12′W / 71.4°N 244.2°W / 71.4; -244.224Lake Towada, Japan
Tsomgo Lacus86°24′S 162°24′W / 86.4°S 162.4°W / -86.4; -162.459Lake Tsomgo, India
Urmia Lacus39°16′S 276°33′W / 39.27°S 276.55°W / -39.27; -276.5528.6Lake Urmia, Iran
Uvs Lacus69°36′N 245°42′W / 69.6°N 245.7°W / 69.6; -245.726.9Uvs Nuur, Mongolia
Vänern Lacus70°24′N 223°06′W / 70.4°N 223.1°W / 70.4; -223.143.9Vänern, Sweden
Waikare Lacus81°36′N 126°00′W / 81.6°N 126.0°W / 81.6; -126.052.5Lake Waikare, New Zealand

Lakebed names of Titan

NameCoordinatesLength (km)[note 1]Source of name
Atacama Lacuna62°48′N 227°36′W / 62.8°N 227.6°W / 62.8; -227.635.9Atacama Desert and associated salt pans
Eyre Lacuna72°36′N 225°06′W / 72.6°N 225.1°W / 72.6; -225.125.4Lake Eyre, Australia
Jerid Lacuna66°42′N 221°00′W / 66.7°N 221°W / 66.7; -22142.6Chott el Djerid, Tunisia
Kutch Lacuna88°24′N 217°00′W / 88.4°N 217°W / 88.4; -217175Great Rann of Kutch, India-Pakistan
Melrhir Lacuna64°54′N 212°36′W / 64.9°N 212.6°W / 64.9; -212.623Chott Melrhir, Algeria
Nakuru Lacuna65°49′N 94°00′W / 65.81°N 94°W / 65.81; -94188Lake Nakuru, Kenya
Ngami Lacuna66°42′N 213°54′W / 66.7°N 213.9°W / 66.7; -213.937.2Lake Ngami, Botswana
Racetrack Lacuna66°06′N 224°54′W / 66.1°N 224.9°W / 66.1; -224.99.9Racetrack Playa, USA
Uyuni Lacuna66°18′N 228°24′W / 66.3°N 228.4°W / 66.3; -228.427Salar de Uyuni, Bolivia
Woytchugga Lacuna68°53′N 109°00′W / 68.88°N 109°W / 68.88; -109449Lake Woytchugga, Australia
Veliko Lacuna76°48′S 33°06′W / 76.8°S 33.1°W / -76.8; -33.193Veliko Lake, Bosnia and Herzegovina

Bay names of Titan

NameCoordinatesLiquid bodyLength (km)[note 1]Source of name
Arnar Sinus72°36′N 322°00′W / 72.6°N 322°W / 72.6; -322 (Arnar Sinus)Kraken Mare101Arnar, fjord in Iceland
Flensborg Sinus64°54′N 295°18′W / 64.9°N 295.3°W / 64.9; -295.3 (Flensborg Sinus)Kraken Mare115Flensburg, fjord between Denmark and Germany
Gabes Sinus67°36′N 289°36′W / 67.6°N 289.6°W / 67.6; -289.6 (Gabes Sinus)Kraken Mare147Gabes, or Syrtis minor, a bay in Tunisia
Kumbaru Sinus72°36′N 322°00′W / 72.6°N 322°W / 72.6; -322 (Kumbaru Sinus)Kraken Mare122Bay in India
Moray Sinus76°36′N 281°24′W / 76.6°N 281.4°W / 76.6; -281.4 (Moray Sinus)Kraken Mare204Moray Firth in Scotland
Nicoya Sinus74°48′N 251°12′W / 74.8°N 251.2°W / 74.8; -251.2 (Nicoya Sinus)Ligeia Mare130Gulf of Nicoya in Costa Rica
Okahu Sinus73°42′N 282°00′W / 73.7°N 282°W / 73.7; -282 (Okahu Sinus)Kraken Mare141Okahu Bay near Auckland, New Zealand
Patos Sinus77°12′N 224°48′W / 77.2°N 224.8°W / 77.2; -224.8 (Patos Sinus)Ligeia Mare103Patos, fjord in Chile
Puget Sinus82°24′N 241°06′W / 82.4°N 241.1°W / 82.4; -241.1 (Puget Sinus)Ligeia Mare93Puget Sound in Washington, United States
Rombaken Sinus75°18′N 232°54′W / 75.3°N 232.9°W / 75.3; -232.9 (Rombaken Sinus)Ligeia Mare92.5Rombaken, fjord in Norway
Skelton Sinus76°48′N 314°54′W / 76.8°N 314.9°W / 76.8; -314.9 (Skelton Sinus)Kraken Mare73Skelton Glacier near Ross Sea, Antarctica
Trold Sinus71°18′N 292°42′W / 71.3°N 292.7°W / 71.3; -292.7 (Trold Sinus)Kraken Mare118Trold Fiord Formation in Nunavut, Canada
Tunu Sinus79°12′N 299°48′W / 79.2°N 299.8°W / 79.2; -299.8 (Tunu Sinus)Kraken Mare134Tunu, fjord in Greenland
Wakasa Sinus80°42′N 270°00′W / 80.7°N 270°W / 80.7; -270 (Wakasa Sinus)Ligeia Mare146Bay in Japan
Walvis Sinus58°12′N 324°06′W / 58.2°N 324.1°W / 58.2; -324.1 (Walvis Sinus)Kraken Mare253Walvis Bay in Namibia

Island names of Titan

InsulaCoordinatesLiquid bodyNamed after
Bermoothes Insula67°06′N 317°06′W / 67.1°N 317.1°W / 67.1; -317.1 (Bermoothes Insula)Kraken MareBermoothes, an enchanted island in Shakespeare's Tempest
Bimini Insula73°18′N 305°24′W / 73.3°N 305.4°W / 73.3; -305.4 (Bimini Insula)Kraken MareBimini, island in Arawak legend said to contain the fountain of youth.
Bralgu Insula76°12′N 251°30′W / 76.2°N 251.5°W / 76.2; -251.5 (Bralgu Insula)Ligeia MareBaralku, in Yolngu culture, the island of the dead and the place where the Djanggawul, the three creator siblings, originated.
Buyan Insula77°18′N 245°06′W / 77.3°N 245.1°W / 77.3; -245.1 (Buyan Insula)Ligeia MareBuyan, a rocky island in Russian folk tales located on the south shore of Baltic Sea
Hufaidh Insulae67°00′N 320°18′W / 67°N 320.3°W / 67; -320.3 (Hufaidh Insulae)Kraken MareHufaidh, legendary island in the marshes of southern Iraq
Krocylea Insulae69°06′N 302°24′W / 69.1°N 302.4°W / 69.1; -302.4 (Kocylea Insulae)Kraken MareCrocylea, mythological Greek island in the Ionian Sea, near Ithaca
Mayda Insula79°06′N 312°12′W / 79.1°N 312.2°W / 79.1; -312.2 (Mayda Insula)Kraken MareMayda, legendary island in the northeast Atlantic
Penglai Insula72°12′N 308°42′W / 72.2°N 308.7°W / 72.2; -308.7 (Penglai Insula)Kraken MarePenglai, mythological Chinese mountain island where immortals and gods lived.
Planctae Insulae77°30′N 251°18′W / 77.5°N 251.3°W / 77.5; -251.3 (Planctae Insulae)Ligeia MareSymplegades, the "clashing rocks" in Bosphorus, which only Argo was said to have successfully passed the rocks.
Royllo Insula38°18′N 297°12′W / 38.3°N 297.2°W / 38.3; -297.2 (Royllo Insula)Kraken MareRoyllo, legendary island in the Atlantic, on verge of unknown, near Antilla and Saint Brandan.

See also

Notes

  1. 1 2 3 4 The USGS web site gives size as a "diameter", but it is actually the length in the longest dimension.

References

  1. 1 2 Coustenis, A.; Taylor, F. W. (21 July 2008). Titan: Exploring an Earthlike World. World Scientific. pp. 154–155. ISBN 978-981-281-161-5. OCLC 144226016. Retrieved 2013-12-29.
  2. ↑ Staff (3 January 2007). "Methane Lakes Found on Saturn's Largest Moon". VOA News. Voice of America. Archived from the original on July 4, 2009. Retrieved 1 November 2014.
  3. 1 2 3 "Titan". USGS planetary nomenclature page. USGS. Retrieved 2013-12-29. External link in |work= (help)
  4. ↑ "Vid Flumina". USGS planetary nomenclature page. USGS. Retrieved 2013-10-24. External link in |work= (help)
  5. ↑ Dermott, Stanley F.; Sagan, Carl (1995). "Tidal effects of disconnected hydrocarbon seas on Titan". Nature. 374 (6519): 238–240. Bibcode:1995Natur.374..238D. doi:10.1038/374238a0. PMID 7885443.
  6. ↑ Bortman, Henry (November 2, 2004). "Titan: Where's the Wet Stuff?". Astrobiology Magazine. Archived from the original on November 3, 2006. Retrieved 2007-08-28.
  7. 1 2 3 Stofan, E. R.; Elachi, C.; et al. (January 4, 2007). "The lakes of Titan". Nature. 445 (1): 61–64. Bibcode:2007Natur.445...61S. doi:10.1038/nature05438. PMID 17203056. Retrieved 2007-08-27.
  8. ↑ Lakdawalla, Emily (June 28, 2005). "Dark Spot Near the South Pole: A Candidate Lake on Titan?". The Planetary Society. Retrieved 2006-10-14.
  9. ↑ "NASA Cassini Radar Images Show Dramatic Shoreline on Titan" (Press release). Jet Propulsion Laboratory. September 16, 2005. Retrieved 2006-10-14.
  10. ↑ "PIA08630: Lakes on Titan". NASA Planetary Photojournal. NASA/JPL. Retrieved 2006-10-14.
  11. ↑ "Titan Has Liquid Lakes, Scientists Report in Nature". NASA/JPL. January 3, 2007. Archived from the original on July 12, 2012. Retrieved 2007-01-08.
  12. ↑ "River networks on Titan point to a puzzling geologic history". MIT. July 20, 2012. Retrieved 2012-07-23.
  13. ↑ Hecht, Jeff (July 11, 2011). "Ethane lakes in a red haze: Titan's uncanny moonscape". New Scientist. Retrieved 2011-07-25.
  14. ↑ Mitri, Giuseppe; Showman, Adam P.; Lunine, Jonathan I.; Lorenz, Ralph D. (February 2007). "Hydrocarbon Lakes on Titan" (PDF). Icarus. 186 (2): 385–394. Bibcode:2007Icar..186..385M. doi:10.1016/j.icarus.2006.09.004.
  15. ↑ Lakdawalla, Emily (2007). "News flash: Lakes at Titan's south pole, too, on top of the land of lakes in the north". The Planetary Society. Retrieved 2007-10-12.
  16. ↑ Wall, Mike (2010-12-17). "Saturn Moon's 'Lake Ontario': Shallow and Virtually Wave-free". Space.Com web site. Retrieved 2010-12-19. External link in |work= (help)
  17. ↑ Foley, James (2013-12-20). "Depth and Volume of Methane Seas on Saturn Moon Titan Calculated". Nature World News. Retrieved 2014-04-14.
  18. ↑ "Titan Has More Oil Than Earth". February 13, 2008. Retrieved 2008-02-13.
  19. ↑ "Astrophile: Titan lake has more liquid fuel than Earth". December 13, 2013. Retrieved 2013-12-14.
  20. ↑ Adam Hadhazy (2008). "Scientists Confirm Liquid Lake, Beach on Saturn's Moon Titan". Scientific American. Retrieved 2008-07-30.
  21. ↑ Hecht, Jeff (July 11, 2011). "Ethane lakes in a red haze: Titan's uncanny moonscape". New Scientist. Retrieved 2011-07-25.
  22. ↑ Hecht, Jeff (August 6, 2014). "Saturn Moon May Host its own Dead Sea". New Scientist. Retrieved 2014-08-23.
  23. ↑ Wenz, John (March 17, 2018). "Weird crystals could coat Titan". New Scientist. Retrieved 2018-03-23.
  24. ↑ "The bathymetry of a Titan sea". Geophysical Research Letters. 41: 1432–1437. March 16, 2014. Bibcode:2014GeoRL..41.1432M. doi:10.1002/2013GL058618. Retrieved 2016-05-08.
  25. ↑ "Adhesion, plasticity and other peculiar properties of solid methane". Cryogenics. 52: 325–330. February 1, 2012. Bibcode:2012Cryo...52..325K. doi:10.1016/j.cryogenics.2012.02.001. Retrieved 2012-02-01.
  26. ↑ "Blocks of Hydrocarbon Floating on Titan's Lakes?". February 8, 2013. Retrieved 2013-01-10.
  27. ↑ Greicius, Tony (March 15, 2017). "Experiments Show Titan Lakes May Fizz with Nitrogen". NASA. Retrieved 2017-04-21.
  28. ↑ Hand, Eric (December 16, 2014). "Spacecraft spots probable waves on Titan's seas". Science. Retrieved 2015-01-14.
  29. ↑ Hecht, Jeff (February 22, 2013). "Icy Titan spawns tropical cyclones". New Scientist. Retrieved 2013-03-09.
  30. ↑ "Surface roughness of Titan's hydrocarbon seas". Earth and Planetary Science Letters. 474: 20–24. September 15, 2017. Bibcode:2017E&PSL.474...20G. doi:10.1016/j.epsl.2017.06.007. Retrieved 2018-04-08.
  31. ↑ Grossman, Lisa (2009-08-21). "Saturn moon's mirror-smooth lake 'good for skipping rocks'". New Scientist web site. Retrieved 2009-11-25.
  32. ↑ Wye, L. C.; Zebker, H. A.; Lorenz, R. D. (2009-08-19). "Smoothness of Titan's Ontario Lacus: Constraints from Cassini RADAR specular reflection data". Geophysical Research Letters. American Geophysical Union. 36 (16): L16201. Bibcode:2009GeoRL..3616201W. doi:10.1029/2009GL039588. Retrieved 2009-11-25.
  33. ↑ Cook, J.-R. C. (2009-12-17). "Glint of Sunlight Confirms Liquid in Northern Lake District of Titan". NASA web site Cassini mission page. NASA. Retrieved 2009-12-18. External link in |work= (help)
  34. ↑ Lakdawalla, Emily (17 December 2009). "Cassini VIMS sees the long-awaited glint off a Titan lake". The Planetary Society Blog. Planetary Society. Retrieved 2009-12-17. External link in |work= (help)
  35. ↑ "Titan probe's pebble 'bash-down'". BBC News. April 10, 2005. Retrieved 2007-08-06.
  36. ↑ Lakdawalla, Emily (January 15, 2005). "New Images from the Huygens Probe: Shorelines and Channels, But an Apparently Dry Surface". The Planetary Society. Archived from the original on August 29, 2007. Retrieved 2005-03-28.
  37. ↑ R.Lorenz, C.Sotin, (2010). "The Moon That Would be a Planet". Scientific American. 302 (3): 36–43. Bibcode:2010SciAm.302c..36L. doi:10.1038/scientificamerican0310-36. PMID 20184181.
  38. ↑ C.Griffith; et al. (2012). "Possible tropical lakes on Titan from observations of dark terrain". Nature. 486: 237–239. Bibcode:2012Natur.486..237G. doi:10.1038/nature11165.
  39. ↑ "Tropical Methane Lakes on Saturn's Moon Titan". saturntoday.com. 2012. Retrieved 2012-06-16.
  40. ↑ "Tropical Titan". astrobio.net. 2007. Retrieved 2007-10-16.
  41. ↑ "New Computer Model Explains Lakes and Storms on Titan". saturntoday.com. 2012. Retrieved 2012-01-26.
  42. ↑ "Soggy bogs swallow craters on Titan". www.newscientist.com. 2013. Retrieved 2013-10-29.
  43. ↑ "Icy Aquifers on Titan Transform Methane Rainfall". saturntoday.com. 2013. Retrieved 2014-09-03.
  44. ↑ "New Views of Titan's Land of Lakes". saturntoday.com. 2013. Retrieved 2013-12-18.
  45. ↑ Stofan, Ellen (25 August 2009). "Presentation to Decadal Survey". Space Policy Online. Retrieved 2009-11-04. |contribution= ignored (help)
  46. ↑ Vastag, Brian (20 August 2012). "NASA will send robot drill to Mars in 2016". Washington Post.
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