Titan News 2021
April 11, 2021: How To Interpret The Absence Of Bottom Echo In Kraken Mare Determined From The Cassini Radar Altimeter Data ?
A recent study has revealed that Kraken Mare may be remarkably deep thanks to data obtained from the Cassini orbiter on the basis of the Radar Altimeter. In fact, Kraken Mare which represents the largest sea on Saturn's largest moon Titan may be several hundred meters deep or around 1,000 feet deep. A new analysis entitled "The Challenging Depths of Titan's Seas", published in the Journal of Geophysical Research: Planets on April 9, 2021 and proposed by Ralph D. Lorenz brings us key information to interpret the absence of bottom echo in Kraken Mare. Several hypotheses can be advanced to try to explain the phenomenon. In the first hypothesis, the absence of bottom echo implies that the sea appears too deep for the identification of a bottom echo. In the second hypothesis, the liquid of the lake contains a relatively significant fraction of ethane so that any radar signal will tend to be absorbed by the liquid. In the third hypothesis, the sea is very deep and contains a relatively significant fraction of ethane. Methane appears to be the main molecule of the seas, lakes or rivers on Titan but ethane and molecular nitrogen can also be present in relatively significant concentrations within the seas, lakes or rivers.
Planetologists believe that the seas, lakes or rivers on the Opaque Moon Titan contain a mixture of methane, ethane and molecular nitrogen. The composition of that mixture can vary depending on the latitude, the area or the season. Methane can be compared to water on Earth since it is the key molecule of the meteorological cycle of Titan. Like water on Earth, methane on Titan can evaporate, form clouds or fall as rain. Methane whose chemical composition is CH4 may be particularly volatile on Titan. Ethane whose chemical formula is C2H6 may be less volatile than methane and may be comparable to salt on Earth. Ethane on Titan must represent a substance that tends to remain in the bed of any sea, lake or river even if the evaporation process of methane is relatively strong. Some ancient seas on Earth have kept their salt over time. Ethane may follow the same logic on Titan as salt on the Blue Planet. The mysterious seas, lakes and rivers of Titan must be remarkably diverse. Researchers try to gather new clues regarding those liquid bodies on the basis of the huge amount of data acquired from the Huygens probe on January 14, 2005 and acquired from the Cassini spacecraft during its long mission in the Saturn System, from 2004 to 2017.
The image above represents a portion of a radar swath obtained on February 22, 2007 from the Cassini orbiter during the T25 Flyby. Each side of the image represents 100 km. The view unveils a portion of Kraken Mare where Moray Sinus can be found in particular. One can clearly discern a well-defined coastline which appears quite irregular. Credit for the original radar view: NASA/JPL/Cassini RADAR Team/Jason Perry.
April 8, 2021: A New Study Involving Kaitlyn Loftus Reveals That The Size Of Alien Raindrops Like The Raindrops On Titan May Be Relatively Similar To The Size Of Typical Raindrops On Earth
A new study entitled "The Physics of Falling Raindrops in Diverse Planetary Atmospheres", published in AGU's Journal of Geophysical Research: Planets on March 15, 2021 and involving Kaitlyn Loftus and Robin Wordsworth reveals that the various raindrops potentially encountered on other worlds in the Solar System or beyond are relatively similar in terms of size. A raindrop must be big enough to reach the surface of any planet or moon. If that raindrop is too big, it will tend to break up into smaller raindrops. Obviously, any atmosphere has its particularities. For instance, the atmosphere of Titan is dominated by molecular nitrogen like the atmosphere of the Earth but it contains a relatively significant concentration of methane, a molecule that is relatively scarce in the atmosphere of the Earth. In the harsh environment of Titan, methane can form clouds which can engender rainfall events like on Earth. Planetologists try to imagine or anticipate the characteristics of raindrops on Titan. The new research work makes things clearer regarding the physics, the dynamics or the chemistry of raindrops on other worlds like Jupiter, Saturn, Titan, Uranus or Neptune. Theories, simulations or models are likely to tell us a lot regarding the potential reality of other worlds.
In order to anticipate or determine the behavior of raindrops, we must understand fluid dynamics and thermodynamics. The physics of raindrops can be applied to raindrops of water in our own atmosphere, raindrops of methane in the atmosphere of Saturn's largest moon Titan, raindrops of sulfuric acid in the atmosphere of Venus, raindrops of helium in the atmosphere of Jupiter, raindrops of pure carbon in the form of diamonds in the atmosphere of Neptune or even raindrops of iron or quartz on potential exoplanets where the environmental temperature is extremely high. On the Red Planet Mars, raindrops of water can't be encountered but snowfall events involving carbon dioxide or dry ice can take shape. On the Gas Giant Jupiter, mushy ammonia hailstones can potentially fall. The researchers show that the raindrop size in any atmosphere will imply a particular shape of the raindrop, a particular terminal velocity of the raindrop and a particular evaporation rate of the raindrop. In other words, the planetologists are in a position to determine these three characteristics of the raindrop on the basis of its initial size. Will the raindrop released by the cloud reach the surface on the basis of its size, on the basis of its evaporation rate or on the basis of its speed ?
The image in the upper part of the table, whose file name is N00164616.jpg, reveals a portion of the disk of Saturn's largest moon Titan obtained during the Cassini mission in the Saturn System on October 18, 2010 from the Cassini orbiter on the basis of the CL1 filter and of the CB3 filter. The image had not been validated or calibrated at the time of the observation and a validated or calibrated version was going to be archived with the Planetary Data System proposed by NASA. One can notice a large system of clouds at a low or mid-latitude of the Opaque Moon. Clouds at those latitudes are generally relatively rare. The clouds observed here may be related to seasonal factors. The image in the lower part of the table represents a colorized version of the original view. Credit for the original view: NASA/JPL-Caltech/Space Science Institute. Credit for the colorization process of the original view: Marc Lafferre, 2021.
March 19, 2021: A New Study Suggests That Enceladus And Titan May Have Taken Shape Much Farther From Saturn Than Their Current Orbit
A new research work entitled "Formation Conditions of Titan's and Enceladus's Building Blocks in Saturn's Circumplanetary Disk", published in The Planetary Science Journal on March 12, 2021 and proposed by Sarah E. Anderson, Olivier Mousis and Thomas Ronnet reveals that Enceladus and Titan may have formed and developed in a circumplanetary disk that appeared much farther from Saturn than the orbit of Enceladus or Titan today. Enceladus is a tiny moon which evolves at a mean distance of 237,948 kilometers from the Ringed Planet Saturn whereas Titan is a giant moon which evolves much farther from Saturn at a mean distance of 1,221,870 kilometers from the Gas Giant. Mimas which is smaller than Enceladus evolves closer to Saturn than Enceladus. There are several major moons located between the orbit of Enceladus and the orbit of Titan. Those major moons are Tethys, Dione and Rhea. Rhea is bigger than Dione and Dione is bigger than Tethys. Thus, until the orbit of Titan, the moons tend to be bigger and bigger as we go away from the Ringed Planet. The orbit of Iapetus, another major moon of Saturn, is found much farther from Saturn than Titan. But Iapetus appears to be much smaller than Titan.
The new study shows that Enceladus and Titan may have formed and developed in a circumplanetary disk (CPD) that was not located at the level of their current orbit. That circumplanetary disk may have been found much farther from Saturn than the orbit of its largest moon Titan. The simulations proposed by the team of Sarah E. Anderson suggest that the disk may have had a radius representing a value found in the range between 66 Saturnian radii and 100 Saturnian radii. The mean radius of the second largest planet in the Solar System represents 58,232 km. Therefore, the lower limit of that presumed circumplanetary disk is equal to 3,843,312 km and the upper limit of that presumed circumplanetary disk is equal to 5,823,200 km. In any configuration of that CPD, the mean distance between that disk and Saturn is much higher than the mean distance between Titan and Saturn. Enceladus and Titan are thought to have formed and developed long ago in the period of the formation of the Solar System. The Solar System formed about 4.6 billion years ago. The center of gravity of the Solar System became the Sun, the only star of the Solar System. A circumstellar disk gave birth to the planets we know today. Around most of those planets, smaller worlds or moons took shape as well.
The image above reveals a portion of Saturn, a portion of its rings as well as the Orange Moon Titan in front of the Gas Giant. The view was generated on the basis of data obtained with the Narrow-Angle Camera of the Cassini spacecraft on May 21, 2011, at a distance of about 1.4 million miles or 2.3 million kilometers from the Opaque Moon. The images mobilized to produce the color view were captured using red, green and blue spectral filters. One can notice the remarkable contrast between the color of Titan's atmosphere and the color of Saturn's atmosphere in particular. Image credit: NASA/JPL-Caltech/Space Science Institute.
March 4, 2021: Titan May Contain Several Types Of Lakes, Seas Or Oceans
Saturn's largest moon Titan represents the only world beyond the Earth, in the Solar System, known to harbor stable pools of liquids on its surface. That's why that giant moon of the Ringed Planet represents a key target in terms of exploration for planetologists. Some researchers and engineers are currently preparing Dragonfly, a new mission to Titan. The Dragonfly probe will be in a position to fly and to explore its environment when it lands on Titan in the 2030's. Thanks to the Cassini spacecraft and thanks to the Huygens probe, we have gathered a huge amount of data regarding the atmosphere, the surface, the chemistry or the upper layers of the Orange Moon. The long mission of the Cassini spacecraft and the intense mission of the Huygens probe have allowed us to better understand the exotic atmosphere of that icy world. We have become aware that Titan is really a complex world which can be compared to a puzzle. Researchers try to gather new clues in order to improve our level of understanding of Saturn's largest moon. Prior to the Cassini-Huygens mission, some researchers had imagined that there may be seas or oceans of methane or ethane in the harsh environment of the Opaque Moon. Was the Earth the only world in the Solar System to contain oceans ?
The Cassini-Huygens mission has brought us clear answers regarding the potential presence of stable lakes, seas, oceans or rivers on Saturn's largest moon. The radar views as well as the infrared or near-infrared views obtained from the Cassini orbiter have clearly shown that there are lakes, seas or rivers in the high latitudes of each hemisphere on the Opaque Moon. Researchers did not expect the surprising distribution of lakes, seas or rivers on that enigmatic world. The Huygens probe obtained, during its atmospheric descent on Titan on January 14, 2005, remarkable panoramic views unveiling a sharp contrast between relatively bright areas and relatively dark areas. One could clearly identify a network of dark drainage channels within the bright hills observed from the parachuted probe. One could also discern a dark or brown plain marking a sharp contrast with the bright hills. Some specialists or researchers had thought, on the basis of the black-and-white views, that the dark or brown plain was in fact a sea of liquid methane. The color view obtained from the surface clearly showed that the probe had not landed onto a sea or ocean. Was the area of the landing site an ancient sea or ocean ?
The image in the upper part of the table represents a raw view of a portion of Saturn's largest moon Titan. The image whose file name is W00014169.jpg was acquired on March 18, 2006 from the Cassini spacecraft on the basis of the CB3 filter and of the CL2 filter. The view had not been validated or calibrated at the time of the observation and a validated or calibrated version was going to be archived with the Planetary Data System proposed by NASA. The image in the lower part of the table represents a colorized version of the original view. One can notice the sharp contrast between a bright area and a dark area in particular. Are the dark areas found in the low or mid-latitudes ancient seas or oceans ? Credit for the original view: NASA/JPL-Caltech/Space Science Institute. Credit for the colorization process of the original view: Marc Lafferre, 2021.
February 20, 2021: Some Researchers Characterize A New Form Of Ice That May Be Present Beneath The Surface Of Icy Worlds Like Europa Or Titan
A new study entitled "Structural characterization of ice XIX as the second polymorph related to ice VI", proposed by a group of researchers involving Thomas Loerting and published in the journal Nature Communications on February 18, 2021 reveals the discovery or the characterization of a new form of ice taking shape in environments undergoing extremely high pressures. The new form of ice is now known as ice XIX. Until now, scientists have been in a position to identify 19 ice polymorphs or 19 forms of ice. The typical ice that we regularly encounter on Earth unveils an hexagonal shape of oxygen atoms. The common hexagonal form of ice is characterized by hydrogen disorder and geometric frustration. The hydrogen atoms which are connected to the oxygen atoms of the hexagon tend to be disordered or tend to have irregular positions due to a relatively high dynamics. There are numerous configurations of the lattice at relatively high temperatures below the freezing point of water around minus 10 degrees Celsius. The ice we encounter on Earth is in fact a relatively dynamic molecular structure compared to the other forms of ice one can encounter in nature. The behavior of ice can significantly change if the environmental pressure is much higher.
In the Outer Solar System, the environmental conditions are likely to allow the presence of other forms of ice. The high pressures encountered in the atmosphere of Jupiter or Saturn are likely to allow the development of other types of molecules than what we usually encounter on Earth. Most moons of Saturn are extremely rich in water ice and at a certain depth, new types of water ice can potentially be found. Mimas, Enceladus, Tethys, Dione and Rhea are bright moons unveiling an external crust dominated by water ice. A world like Titan appears to be more varied than the other moons of the Ringed Planet Saturn but its external crust may also be rich in water ice. Therefore, those moons may unveil some forms of ice that can take shape in environments dominated by relatively high pressures. Even if most of the icy worlds found in the Outer Solar System are devoid of any significant atmosphere, some forms of ice like ice XIX can potentially be encountered beneath the surface of those worlds. The typical form of water ice may be widespread in the upper layer of icy worlds like Europa or Titan but at a relatively high depth beneath the surface of those moons, some exotic forms of water ice may be found due to relatively high pressures.
The image above reveals Saturn's largest moon Titan and Rhea, another major moon of the Ringed Planet, at scale. The original image of Titan whose file name is N00205583.jpg represents a raw view obtained from the Cassini orbiter on April 13, 2013 on the basis of the CL1 filter and of the UV3 filter. The original image of Rhea was acquired in visible light with the Wide-Angle Camera of the Cassini spacecraft on November 21, 2009. Titan and Rhea may unveil various types of water ice. Credit for the original view of Titan: NASA/JPL-Caltech/Space Science Institute. Credit for the original view of Rhea: NASA/JPL/Space Science Institute. Montage credit: Marc Lafferre, 2021.
January 30, 2021: The Dragonfly Mission May Bring Us Major Clues Upon The Origin Of The Methane Present On The Opaque Moon Titan
Thanks to the Cassini-Huygens mission, our level of understanding of Titan's environment has significantly improved. However, many mysteries regarding Saturn's largest moon have emerged thanks to the analysis of the huge amount of data gathered by the Cassini orbiter or the Huygens probe. Remarkable panoramic images of Titan's surface had been acquired from the parachuted probe during its historic atmospheric descent on January 14, 2005. The color view obtained from the surface captures our imagination. The aerial views obtained from the Huygens probe had unveiled a familiar landscape composed of bright hills containing a network of dark drainage channels and composed of a brown or dark plain reminiscent of a dried up sea or lake. The journey of the Cassini orbiter ended on September 15, 2017 with the final plunge of the spacecraft into the atmosphere of the Ringed Planet Saturn. A new mission to Saturn's largest moon Titan is starting to take shape. That mission which involves Elizabeth Turtle of the Johns Hopkins University Applied Physics Laboratory, the Principal Investigator of the mission, is known as the Dragonfly mission. That challenge is very ambitious since the mission will mobilize a rotorcraft to explore the environment of the Opaque Moon.
The data gathered by the Dragonfly rotorcraft may allow us to better understand the various chemical reactions taking shape on the ground or in the dense air near the soil or in the troposphere of the Orange Moon. The mission may provide major clues to the habitability of Saturn's largest moon. Can the environment of Titan engender complex molecules, prebiotic molecules or some typical molecules mobilized by our biosphere ? The Dragonfly mission may allow us to get a clearer understanding of the complex chemistry of Titan. The Dragonfly mission is expected to last at least 32 months and may last longer if the probe or if the instruments continue to correctly work in the harsh environment of the giant moon where the level of energy received from the Sun is much lower than the level of energy received at the level of the Earth. The flying robot or the drone will represent an "8-bladed rotorcraft". That drone will evolve in an environment where the air is several times denser than the air on Earth at sea level and where the gravity is much lower than on Earth. Therefore, it will need less energy than on Earth to fly. In other words, the rotation speed of the rotor can be slower on Titan than on Earth.
The image above represents a portion of a radar swath of Titan obtained from the Cassini orbiter on June 20, 2011 during the T77 Flyby. Each side of the portion is 100 km long. One can notice a relatively circular feature which may correspond to an impact crater or a cryovolcano. One can also notice relatively linear and parallel dunes in the left part of the view. The contrast between the area of the dunes and the area of the circular feature is remarkable. Credit for the original view: NASA/JPL/Cassini RADAR Team/Jason Perry. Montage credit: Marc Lafferre, 2021.
January 23, 2021: Water Can Be Found In The Form Of Clathrate Hydrates On The Surface Of Titan And In The Form Of Ice On The Surface Of Europa According To A New Study
A new study entitled "On the Occurrence of Clathrate Hydrates in Extreme Conditions: Dissociation Pressures and Occupancies at Cryogenic Temperatures with Application to Planetary Systems", published on December 17, 2020 in The Planetary Science Journal and proposed by a team composed of Hideki Tanaka, Takuma Yagasaki and Masakazu Matsumoto reveals that water can form clathrate hydrates on the surface of Titan and can only form ice on the surface of Europa or Ganymede on the basis of theoretical models. The researchers from the Okayama University in Japan developed a statistical mechanics theory in order to predict or to determine the presence of clathrate hydrates on worlds found in the Outer Solar System where environmental temperatures are particularly low. Water is generally found in the form of ice on the surface of the Earth if the environmental temperature is around or below 0 degree Celsius, 32 degrees Fahrenheit or 273 Kelvin. But water can also form clathrate hydrates if the environmental temperature is sufficiently low and if there is the right combination of atmospheric pressure and environmental temperature. The planetologists of the study have been in a position to determine whether Pluto, Titan, Europa or Ganymede can contain clathrate hydrates on their surface.
The presence, the concentration or the amount of clathrate hydrates are likely to bring us major clues regarding the dynamics, the stability or the evolution of any atmosphere for a world where cryogenic temperatures are encountered in the environment. A clathrate hydrate represents a molecular cage which traps small gaseous molecules. Water can appear as a solid, as a liquid or as a gas on our planet but the molecule can also appear in the form of clathrate hydrates on icy bodies located beyond Mars, in the Outer Solar System. In fact, clathrate hydrates represent a particular type of crystalline solid which looks like the typical water ice we know on Earth. Water molecules are widespread in the Solar System. They can be present on the surface of comets, planets, Dwarf Planets or moons. The small water-based cages contain smaller molecules which allow the structure to keep its shape over time or which prevent the molecular cage from collapsing and from generating the typical water ice we regularly encounter on Earth. The key factors for the formation or for the development of clathrate hydrates are pressure and temperature. Numerous moons of the Outer Solar System are devoid of any atmosphere so that water will tend to form the typical ice we know rather than clathrate hydrates.
The image above reveals the disk of Titan and the disk of Europa at scale. The original view of Titan whose file name is N00191987.jpg represents a raw image obtained from the Cassini spacecraft on June 29, 2012 on the basis of the CL1 filter and of the CB3 filter. The original view of Europa was acquired on September 7, 1996 from the Galileo spacecraft. Water may be present in the form of clathrate hydrates on the surface of Titan and in the form of typical ice on the surface of Europa according to the new study. Credit for the original view of Titan: NASA/JPL-Caltech/Space Science Institute. Credit for the original view of Europa: NASA/JPL/DLR. Montage credit: Marc Lafferre, 2021.
January 21, 2021 : A New Study Involving Valerio Poggiali Implies That The Depth Of Kraken Mare May Reach 1,000 Feet Near Its Center
A recent study entitled « The Bathymetry of Moray Sinus at Titan's Kraken Mare », published on December 4, 2020 in the Journal of Geophysical Research and proposed by a team involving Valerio Poggiali who is a research associate in Cornell Center for Astrophysics and Planetary Science (CCAPS), in the College of Arts and Sciences, suggests that the largest pool of liquids on Titan, Kraken Mare, may be 1,000 feet deep near its center. The determination of the amount of liquid methane present on Titan's surface or beneath the external crust can bring major clues upon the hydrology or the meteorology of Saturn's largest moon. Researchers have mobilized the Radar Mapper or the Radar Altimeter of the Cassini spacecraft in order to determine the depth of pools of liquids like Ligeia Mare and Kraken Mare. Kraken Mare, Ligeia Mare and Punga Mare appear to be the largest lakes or seas in the high latitudes of the northern hemisphere. The high latitudes of the northern hemisphere appear to be much more humid than the high latitudes of the southern hemisphere which appear much more humid than the low or mid-latitudes of the giant moon. The pools of liquids in the north polar region are likely dominated by methane.
Thanks to the low environmental temperature and thanks to the relatively high atmospheric pressure on Titan's surface, methane and ethane can appear in their liquid form on the surface. The atmosphere of Titan, dominated by molecular nitrogen, contains a relatively significant concentration of methane. That's why researchers have long imagined or anticipated the presence of liquid methane or liquid ethane on the surface of the Opaque Moon. Ontario Lacus was the first pool of liquids clearly identified on Titan. Later, the lakes, seas and rivers of the high latitudes of Titan's northern hemisphere were unveiled by the radar data or the infrared or near-infrared data acquired from the Cassini orbiter. Kraken Mare is by far the largest pool present on the external crust of Titan. Kraken Mare is not a pond because its maximum depth is relatively high. The team of Valerio Poggiali, composed of Alex Hayes, professor of astronomy and director of CCAPS, Jonathan Lunine, the David C. Duncan Professor in the Physical Sciences, and chair, Department of Astronomy, Marco Mastrogiuseppe, a former Cornell postdoctoral researcher who is now research associate at Sapienza University of Rome in Italy, Alice Le Gall from the Institut Universitaire de France, Paris and research associates Illeana Gomez-Leal and Daniel Lalich, advanced that Kraken Mare may be well suited for an exploration campaign led by a potential robotic submarine.
The image in the upper part of the table represents a raw view of a portion of Saturn's largest moon Titan unveiling the land of lakes and seas in the northern hemisphere of the giant moon. One can clearly discern some shapes of Kraken Mare, the largest pool of liquids on the surface of the Opaque Moon. The image whose file name is N00289201.jpg was obtained on September 12, 2017 from the Cassini orbiter on the basis of the CL1 filter and of the CB3 filter. The view had not been validated or calibrated at the time of the observation and a validated or calibrated version was going to be archived with the Planetary Data System proposed by NASA. The image in the lower part of the table represents a colorized version of the original view. Credit for the original view: NASA/JPL-Caltech/Space Science Institute. Credit for the colorization process of the original view: Marc Lafferre, 2021.
January 19, 2021 : The Icy Particles Of The Haze Of Pluto May Be Different From The Particles Of The Haze Of Titan According To A New Study Involving Panayotis Lavvas
A new research work entitled « A major ice component in Pluto's haze », published in the journal Nature Astronomy on December 21, 2020 and involving the planetary scientist Panayotis Lavvas from the University of Reims Champagne-Ardenne in France reveals that the icy particles encountered in the haze of the Dwarf Planet Pluto may be different from the particles encountered in the haze of Saturn's largest moon Titan. Titan, Triton and Pluto which are worlds located in the Outer Solar System unveil an atmosphere composed of molecular nitrogen, methane and carbon monoxide. The presence of any atmosphere appears to be closely related to the level of gravity and to the level of energy received from the Sun or to the environmental temperature. A world on which the environmental temperature is relatively low will have a higher probability to contain an atmosphere than a world on which the environmental temperature is relatively high. A world that is more massive than another world will also have a higher probability to contain an atmosphere than the lighter world or the less massive world. Titan reveals a completely opaque atmosphere due to the presence of a haze rich in organics or hydrocarbons.
Researchers are particularly interested in the dynamics, the nature and the chemical activity of Titan's haze because that haze can produce complex molecules via the interactions between the radiations generated by the Sun and the various particles, compounds, ions or molecules found in the haze. Planetologists have noticed that there is a complex photochemical activity in the upper atmosphere of the Orange Moon under the influence of ultraviolet light from the Sun. We can clearly notice the sharp contrast between the orange ball of Titan and the blue or purple upper layers of the deep and thick atmosphere. Relatively complex hydrocarbons or organics can take shape in the upper atmosphere of Titan thanks to the photochemical activity. The atmosphere of the largest moon of Neptune Triton and of the Dwarf Planet Pluto also contains a haze or hazes engendered by photochemical processes. N2, CH4 and CO are regularly identified on the surface or in the atmosphere of the worlds found in the Outer Solar System. The images captured by the New Horizons probe had clearly revealed a field of ice rich in nitrogen ice and carbon monoxide ice for instance. Methane ice had also been identified on Pluto's surface.
The image above reveals the disk of Titan and the disk of Pluto at scale. One can clearly notice the blue upper layers of the atmosphere of Titan as well as the various layers of the blue atmosphere of the Dwarf Planet Pluto. The original view of Titan which represents a raw image whose file name is W00091693.jpg was obtained from the Cassini orbiter on February 12, 2015 on the basis of the CL1 filter and of the VIO filter. The original view of Pluto was generated on the basis of data acquired from the New Horizons spacecraft during its historic flyby on July 14, 2015. The colors of the disk of Titan are artificial. Credit for the original view of Titan: NASA/JPL-Caltech/Space Science Institute. Credit for the original view of Pluto: NASA/JHUAPL/SwRI. Credit for the montage: Marc Lafferre, 2021.
January 1, 2021 : A New Study Involving Scot C. R. Rafkin Reveals The High Complexity Of Air-Sea Interactions On Titan
A new research work proposed by Scot C. R. Rafkin and Alejandro Soto, recently published in the journal Icarus and entitled « Air-sea interactions on Titan: Lake evaporation, atmospheric circulation, and cloud formation » reveals the high complexity of the various interactions between the lakes or seas and the air on Saturn's largest moon Titan. Evaporation processes, condensation processes and precipitation processes can be encountered on the Opaque Moon like on Earth. A parallel can be drawn between the meteorology of Titan and the meteorology of the Earth even if the key molecule of the meteorological system is different. The meteorology of the Earth is dominated by water (H2O) whereas the meteorology of Titan is dominated by methane (CH4). The mean environmental temperature of the giant moon of the Gas Giant Saturn is much lower than the mean environmental temperature of the Earth so that water can't appear in its liquid form on the surface of Titan in the absence of hot spot. However, the mean environmental temperature of Titan allows the stable presence of liquid methane, liquid ethane or liquid propane on the surface. Thanks to the Cassini-Huygens mission, we know, now, that there are lakes, seas and rivers on Titan.
The lakes, seas or rivers of Titan tend to appear in the high latitudes of each hemisphere. Therefore, the clouds tend to be mostly found at a relatively high latitude of each hemisphere or in the polar areas. Planetologists try to determine the potential interactions between the lakes or seas and the exotic atmosphere. Titan's atmosphere is dominated by molecular nitrogen like our own atmosphere. However, the second most abundant gas of Titan's atmosphere is methane. Oxygen is absent or almost absent in the opaque atmosphere of Saturn's largest moon. Methane represents the key molecule of Titan's hydrology whereas water represents the key molecule of Earth's hydrology. Let's point out that the abundance of liquid methane on Titan's surface is relatively low compared to the abundance of liquid water on the surface of the Blue Planet. The group of researchers revealed the complex mechanisms of the evaporation process between the lakes and the air of the giant moon of the Ringed Planet. Evaporation is in fact governed by a complex process of thermodynamics and dynamics. The scientists also showed that a cold, stable marine layer regularly takes shape in the environment of the pools. The development of clouds on Titan implies special conditions. There may also be very small turbulent fluxes and relatively quiet winds.
The image in the upper part of this table represents a raw view of Saturn's largest moon Titan obtained during the Cassini mission in the Saturn System on August 5, 2016 from the eye of the Cassini spacecraft. The view whose file name is N00264434.jpg was captured on the basis of the CL1 filter and of the CB3 filter. The image had not been validated or calibrated at the time of the observation and a validated or calibrated version was going to be archived with the Planetary Data System proposed by NASA. One can notice, in particular, the relatively dark regions of the low or mid-latitudes as well as dark areas in the lower part of the disk representing seas or lakes dominated by hydrocarbons. The view in the lower part of this table represents a colorized version of the original image. Credit for the original image: NASA/JPL-Caltech/Space Science Institute. Credit for the colorization process: Marc Lafferre, 2021.
Titan News 2020
Titan News 2019
Titan News 2018
Titan News 2017
Titan News 2016
Titan News 2015
Titan News 2014
Titan News 2013
Titan News 2012
Titan News 2011
Titan News 2010
Titan News 2009
Titan News 2008
Titan News 2007
Titan News 2006
Titan News 2004, 2005