Titan News 2017
March 17, 2017 : New Simulations Suggest that Titan's Lakes or Seas May Fizz With Nitrogen
A new study published online in the journal Icarus in February entitled « Laboratory measurements of nitrogen dissolution in Titan lake fluids » and proposed by a team led by Michael Malaska suggests that the lakes or seas of Titan may fizz with nitrogen. This hypothesis is based on experiments simulating the environment of Titan where most lakes, seas or rivers are found. The simulations involved the hydrocarbons methane and ethane as well as nitrogen. The researchers advance that there may be occasional events of spectacular ebullition within the lakes or seas revealing patches of bubbles.
The team of Michael Malaska who is from NASA's Jet Propulsion Laboratory in Pasadena, California simulated the harsh environmental conditions in the land of lakes and seas on Saturn's largest moon and mobilized key ingredients of the lakes or seas that is to say methane, ethane and nitrogen. The specialists observed that significant amounts of nitrogen can be dissolved within liquid methane that can form clouds, fall as rain and form lakes, seas or rivers on Titan. They managed to demonstrate that relatively small changes in temperature, air pressure or composition can engender dissociation of nitrogen from the liquid with bubbles. In other words, the solution of liquid methane or liquid ethane is likely to fizz and to produce bubbles of nitrogen. That's a process resembling the ebullition phenomenon when you open a bottle of carbonated soda.
The data obtained from the Cassini spacecraft reveal that the bodies of liquids on the Opaque Moon are mostly found at high latitudes or in the polar regions, the north polar region appearing to be the most humid area of Titan today. The composition of the lakes or seas can vary depending on the area. Some pools of liquid are mostly composed of methane whereas other bodies of surface liquid are mostly composed of ethane. Michael Malaska advanced : « Our experiments showed that when methane-rich liquids mix with ethane-rich ones - for example from a heavy rain, or when runoff from a methane river mixes into an ethane-rich lake – the nitrogen is less able to stay in solution.» As a result, one can observe numerous bubbles like in a champagne bottle.
Seasonal changes may strongly influence the behavior of nitrogen elements or molecules within the lakes or seas of methane or ethane. If the pools of methane warm slightly due to seasonal factors for instance, the nitrogen compounds present within the liquid may tend to dissociate themselves and to go up to the surface to form bubbles and become an atmospheric gas. Let's point out that the atmosphere is mostly composed of nitrogen like the atmosphere of the Earth. In fact, the hazy atmosphere of Titan rich in methane, in hydrocarbons or organics looks like the presumed atmosphere of the Early Earth. Engineers and scientists who may plan a new mission to Titan with a probe, a lander, a submarine or a drone to the methane or ethane lakes or seas must take into account, in the development of any craft, the fact that the lakes or seas on Titan can potentially be quite fizzy. Excess heat related to the working system of the probe may engender bubbles in the liquid around the craft, in particular at the level of the propellers which propel or orientate the probe. The probe may become hard to control or to steer.
The hypothesis regarding fields of bubbles at the surface or above the lakes or seas had been advanced recently to explain the mystery of the « Magic Islands » which represented bright, transient surface features whose shape had evolved, which had disappeared or reappeared between several radar observations of the same area within the lake or sea near the coast. Several hypotheses had been put forward including the presence of strong waves or evolving materials like icebergs. The radar images obtained from the Radar Mapper of the Cassini spacecraft allow researchers to study the topography, the landscape or the lakes, seas and rivers thanks to brightness variations. One can notice islands for instance within the famous lake or sea Ligeia Mare. But was the Magic Island really an island ? It disappeared so rapidly on the basis of several observations that it is hard to believe it ! In at least one case, we have observed a reappearance of the bright surface features related to the Magic Island phenomenon.
The new study proposed by Michael Malaska and his team brings details regarding basic physical or chemical mechanisms involving key ingredients of Titan's pools and atmosphere and demonstrates, on the basis of relevant or realistic experiments, that the hypothesis for nitrogen bubbles or fizzy lakes or seas must be seriously considered. Jason Hofgartner of JPL who is a co-author of the analysis and who serves as a co-investigator on Cassini's radar team pointed out : « Thanks to this work on nitrogen's solubility, we're now confident that bubbles could indeed form in the seas, and in fact may be more abundant than we'd expected.» It is interesting to analyze the interactions between hydrocarbons and nitrogen which is widespread in planetary atmospheres like the atmosphere of Venus, the Earth or Mars. Could there be a subsurface layer of liquid nitrogen for instance ?
Michael Malaska and his collaborators used liquid ethane in the simulation to simulate a type of sea or lake on Titan. They incorporated nitrogen into the solution which was mainly composed of ethane to see how it behaved. The scientists coaxed nitrogen out of the solution as the ethane molecules froze to the bottom of the tiny body of surface liquid. Solid ethane is denser than liquid ethane whereas solid water or water ice is less dense than liquid water. That's why water ice or icebergs float on liquid water on Earth. This configuration is not possible with solid ethane because it would sink within liquid ethane unless it is made of a lot of empty spaces or pockets inside it. As a result, one can expect that ethane ice would form on the bottom of the Titanian lakes if the physical conditions are met. During the process of crystallization of ethane into ice, the dissolved nitrogen gas will tend to go out and to go up to the surface where it will fizz out or form bubbles.
It's quite hard to imagine a harsh environment where water is as hard as rock with such a dynamics or activity. We have boiling water on Earth and there is probably boiling ethane or boiling methane in the lakes or seas of Titan. How often does it happen ? New questions regarding the lakes, seas and rivers of Titan take shape as the mission advances. Michael Malaska argued that the movement of nitrogen on the Orange Moon doesn't just evolve in one direction. Nitrogen must go into the methane molecules and the ethane molecules before it can be released into the atmosphere. Michael Malaska pointed out : « In effect, it's as though the lakes of Titan breathe nitrogen.» He added : « As they cool, they can absorb more of the gas, 'inhaling'. And as they warm, the liquid's capacity is reduced, so they 'exhale'.» A parallel can be drawn between this mechanism and the process of carbon dioxide absorption by the oceans of the Earth.
The final close flyby of the Hazy Moon by the Cassini spacecraft which will be the 127th targeted encounter with Titan is expected for April 22, 2017. This special flyby has been optimized to perform a remarkable observation campaign of the land of lakes and seas in the northern hemisphere of the Opaque Moon. The Radar Mapper will steer its radar beam toward the northern seas and lakes in order to collect new clues regarding the appearance and the dynamics of the pools of liquids. Will there be changes in the appearance of the coastline or in the albedo of the lakes or seas for instance ? The upcoming radar campaign has been well prepared by the radar team. Researchers should be in a position to analyze potential brightness changes within the lakes or seas. In other words, if features associated with the Magic Island phenomenon are spotted this time, planetologists may be able to determine whether the new bright patches correspond to bubbles, waves, floating materials, icebergs or suspended solids.
The final flyby of Titan performed by the Cassini spacecraft will allow the probe to change or to bend its course to start its final series of 22 plunges through the gap between the Gas Giant Saturn and its innermost rings. This process has been called Cassini's Grand Finale. The Cassini/Huygens spacecraft left our planet in 1997. Therefore, this is a 20-year mission that will end with a spectacular dive of the Cassini spacecraft into Saturn's atmosphere on September 15, 2017. The probe will have studied the dynamics, the nature or the composition of Titan's atmosphere and of Titan's lakes and seas for a long time but for less than a Titanian year which lasts almost 30 Terrestrial years. Now, we know the Summer season in the area of Ontario Lacus in the south polar region but unfortunately, we won't have the opportunity, this time, to perform an in-depth study of the Summer season in the land of lakes and seas of the northern hemisphere because it will only start in a few weeks and it will last around seven Terrestrial years. Will the lake levels diminish due to strong evaporation processes and will the cloud activity increase ? Titan has undoubtedly a lot to teach us.
The image above represents a mosaic view based on near-infrared images acquired during a distant flyby of Titan performed by the Cassini spacecraft on February 17, 2017. On can clearly notice the famous sea Kraken Mare as well as Ligeia Mare and Punga Mare. A bright cloud patch can be identified in the area of Punga Mare in particular. Cirrus-like clouds can also be noticed at mid-latitudes. Is there more evaporation than precipitation in the land of lakes and seas of the north polar region ? Image Credit: NASA/JPL-Caltech/Space Science Institute.
The mosaic view above reveals the area of Ligeia Mare in false color. The view on the right corresponds to Ligeia Mare whereas the four views on the left correspond to an area of Ligeia Mare where a portion of the land seems to have completely disappeared in a relatively short period. The five Synthetic Aperture Radar views obtained with the Radar Mapper of the Cassini spacecraft were obtained between 2007 and 2014. The view on the upper left was taken on April 26, 2007. The second view from top-left was acquired on July 10, 2013. The third view from top-left was captured on August 21, 2014 and the fourth view from top-left was taken on January 11, 2015. A bright patch is present in the second view from top-left but absent in the first view from top-left. In the third view from top-left, it seems to be disintegrating or dissolving and in the fourth view from top-left, it seems to have completely disappeared. What was it ? An exotic iceberg ? A field of bubbles ? Hot springs ? Relatively strong waves ? Image Credit: NASA/JPL-Caltech/ASI/Cornell.
The image above corresponds to an artist's impression of Ligeia Mare where nitrogen bubbles may erupt from the surface of the liquid, from time to time, depending on seasonal factors or meteorological conditions. A slight warming process is likely to engender the release of a significant amount of nitrogen gas from a lake or sea dominated by methane or ethane. If the environmental temperature drops, for instance, the concentration of dissolved nitrogen inside the lake or sea may increase. That's what recent experiments led by Michael Malaska imply. Image Credit: Marc Lafferre, 2017.
- To get further information on that news, go to: https://saturn.jpl.nasa.gov/news/3008/experiments-show-titan-lakes-may-fizz-with-nitrogen.
March 13, 2017 : A New Study Suggests That We May Find An Exotic Lifeform Or Biochemistry On Titan
The Cassini probe and the Huygens probe have gathered a remarkable amount of data regarding Titan since the beginning of the mission inside the Saturnian System in mid-2004 and have revealed an intriguing world unveiling processes which can appear quite familiar to us. The researchers had long suspected the presence of seas or oceans on the surface of Saturn's largest moon and now we can confirm this captivating hypothesis. Titan turns out to be a dynamic world with a varied landscape and a complex atmosphere. Titan is clearly a geologically active world with a limited amount of impact craters as opposed to most moons of the Gas Giant Saturn.
Very few moons in the Solar System have a significant atmosphere. One can mention Triton, the main moon of Neptune and the Smoggy Moon Titan. Ganymede, the largest moon of Jupiter and the largest moon in the Solar System which is a little bit bigger than Titan has no significant atmosphere for instance. That can appear surprising at first sight. We knew that the opaque atmosphere of the Orange Moon was mainly composed of molecular nitrogen with a significant fraction of methane. We now know that a complex organic chemistry can be generated in this exotic atmosphere where clouds or cyclones can be found, in particular at high latitudes.
The Huygens probe landed at a low latitude, in the Adiri/Shangri-La region where bright areas and dark areas can be identified. The aerial views unveiled dark fractures, canyons or drainage channels on bright hills. Researchers and the general public became aware that rainfall can occur in the area engendering rivers or brooks. The probe did not land on a sea or ocean but the images acquired from the landing spot revealed eroded stones or pebbles implying that the landing site may be a dried-up river or brook. In fact, the infrared or near-infrared images as well as the radar views obtained from the Cassini spacecraft have shown that most lakes and seas are found in the high latitudes or in the polar regions of the giant moon. Thre north polar region is clearly the most humid region of Titan. Why ? That's a major question scientists are trying to bring a convincing answer.
Like several moons or Dwarf Planets in the Solar System like Europa, Ganymede, Enceladus, Triton or Pluto, Titan may contain an internal ocean of liquid water which may be salty like the ocean on our planet. Therefore, several liquids may be found in large amounts on or inside Titan, methane, ethane and water beneath the icy crust. Titan has a meteorological cycle of methane comparable to the water cycle of our planet. There are seas, lakes, rivers, canyons, dune fields, mountains and erosional processes via winds, rainfall or snowfall like on Earth. The atmosphere of Titan may be quite similar to the atmosphere of the Early Earth. That's why we often say that Titan is a « prebiotic laboratory ».
Is there a lifeform or biochemistry on Titan or inside Titan ? The Cassini/Huygens mission has not allowed researchers to provide a clear answer to this question but it strengthens our will to deepen our study of Titan. Titan has a great potential to provide significant clues regarding the complex chemistry of carbon or organics. Sarah Hörst who is a planetary researcher with Johns Hopkins University in Baltimore pointed out in a paper entitled « Titan's Atmosphere and Climate » published in an upcoming edition of the Journal of Geophysical Research : « The combination of organics and liquid, in the form of water in a subsurface ocean and methane/ethane in the surface lakes and seas, means that Titan may be the ideal place in the solar system to test ideas about habitability, prebiotic chemistry, and the ubiquity and diversity of life in the universe. »
Can there be two or three lifeforms on and inside Titan since there may be two or three types of stable liquids ? The lakes, seas and rivers of the polar regions may be mainly dominated by a mixture of methane and ethane. As a result, we may find a lifeform or a biochemistry based on liquid methane or liquid ethane at the level of lakes, seas and rivers. The hypothetical ocean of liquid water may harbor a lifeform based on liquid water. Some researchers had advanced the hypothesis for a subsurface layer of liquids dominated by ammonia. Can we also envisage a lifeform based on ammonia ? That's a question we can't rule out. The large amount of organics present on the surface may progressively migrate downward toward the hypothetical subsurface ocean of water representing a significant nutrient source for the hypothetical lifeforms of the subsurface ocean. Thus, a methane cycle between the subsurface ocean, the ground and the atmosphere may occur.
Titan appears to be a soup of organics and hydrocarbons. The atmosphere engenders complex organics which appear in the haze or smog and can fall to the surface where they produce tholins, a kind of orange or red mud or sediment rich in organics. What type of organics can we find ? Are there amino acids on Titan since those molecules appear to be the building blocks of proteins and life on Earth ? The environmental temperature at the level of the surface on Titan is extremely low. That's why chemical reactions will be largely slower than the chemical reactions on Earth. However, Titan has all the ingredients of life as we know it that's to say carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. We are CHNOPS on Earth which means that we are mainly composed of the 6 elements mentioned here !
The hydrocarbons of Titan may be abiogenic as opposed to the hydrocarbons on Earth which are the outcome of ancient life. Methane and ethane which appear in the form of gas on Earth will appear in their liquid form on the surface of Titan because there is the right combination of environmental temperature and atmospheric pressure at the level of the surface. On the surface of the Earth, the environmental temperature is largely too high for methane or ethane to appear in their liquid form. There may be more hydrocarbons on Titan than on Earth. We'll have to sample the haze of Titan because it may resemble the prebiotic environment of the Early Earth as advanced in a 2015 NASA Astrobiology Strategy report.
Elizabeth Turtle who is a planetary scientist with the John Hopkins University Applied Physics Laboratory in Laurel, Maryland pointed out : « Titan gives us the opportunity to search for signatures of life in multiple types of systems - familiar water-based life, but also a biological system that may have developed with hydrocarbon as a solvent.» Britney Schmidt, another planetary scientist of Georgia Tech advanced that Saturn's largest moon provides many examples of captivating or intriguing organic chemistry analyses with alternative structures. She argued : « The Titan example is fantastic because you have a sedimentary process like a terrestrial planet, but it's ice involved.» She added : « It's organic in nature, but it is not necessarily biogenic.» Researchers want to have a better idea regarding the boundary between living molecules and non-living molecules.
Planetology needs more in situ exploration of planetary bodies in order to better understand the nature of their soil or atmosphere. If we could send long-lasting rovers to Titan like we did for Mars with Spirit, Opportunity or Curiosity, we would have a better view of its complex chemistry but we can't rely on solar panels at the level of Saturn or Titan. Moons like Triton or Europa are key targets for scientists but every mission to the Outer Solar System represents a significant investment and is complex to achieve. Researchers are now planning a new mission to Europa which may harbor a salty subsurface ocean of liquid water. The last pass of Titan for the Cassini spacecraft will occur in April. Thus, researchers will then have time to envisage a new mission to this fascinating moon. Scientists agree to say that the lakes or seas of Titan deserve a lander, a boat, a balloon or a drone.
The Astrobiology Strategy report pointed out : « The distribution of watery worlds in our solar system and beyond challenges our limited understanding of life's emergence on Earth and encourages us to think about the environmental conditions amenable to life.» The puzzle is still far from being complete. Astrobiologist Kevin Hand of NASA's Jet Propulsion Laboratory in Pasadena, California argued : « What we're trying to do with the exploration of Europa and the ocean worlds is nothing short of revolutionizing science, revolutionizing our understanding of whether or not biology works beyond Earth.» He added : « We know that physics, chemistry and geology all work beyond Earth.» He concluded : « But when it comes to that fourth fundamental science we have yet to make that leap.» Do Kraken Mare, Ligeia Mare or Punga Mare reveal exotic natural processes or an exotic biochemistry ? That's probably the biggest question regarding Titan. And the scenery must be really captivating !
The image above reveals a view of the disk of Saturn's largest moon obtained with the Wide-Angle Camera of the Cassini spacecraft on January 1, 2014. The camera incorporated a spectral filter sensitive to wavelengths of near-infrared light centered at 939 nanometers for this view. The atmosphere of Titan is completely opaque in the visible spectrum but in the infrared or near-infrared spectrum, landscape features can be discerned. One can notice, here, relatively dark patches representing lakes or seas in the high latitudes of the northern hemisphere. Image Credit: NASA/JPL-Caltech/Space Science Institute.
|The image in the upper part of this table reveals the
surface of a north polar lake on Titan. A delta found between mountains
can be seen on the horizon. The lake is probably mainly composed of
methane. The artistic image corresponds to a
simulated view of the area generated on the basis of the
Shape-From-Shading Technique. The image in the lower part of the table
corresponds to a radar view of the area represented in the simulated
photo. A grey arrow was incorporated into the original radar view,
collected with the Radar Mapper of the Cassini probe on October 9, 2006,
to indicate the orientation of the virtual camera producing the
simulated view of the landscape.
Credit for the Artist's Impression:
Marc Lafferre, 2017.
- To get further information on that news, go to: http://www.seeker.com/saturn-moon-titan-may-offer-glimpse-of-life-as-we-dont-know-it-2307762917.html.
January 14, 2017 : Flash-Back On the Remarkable Achievement of the Huygens Probe Which Landed at a Low Latitude On Titan About Twelve Years Ago
Prior to the Cassini-Huygens mission, nobody knew what the landscape of Titan looked like because the hazy or smoggy atmosphere of Saturn's largest moon is completely opaque from outer space. Researchers were fascinated and intrigued by this exotic and unique world which appears to be the second largest moon in the Solar System. Ganymede, the giant moon of Jupiter, is slightly bigger than Titan but paradoxically it is devoid of any significant atmosphere. Crazy or optimistic hypotheses regarding the nature of Titan's surface had been advanced such as the presence of a global ocean of methane or ethane.
Researchers knew that the environmental conditions on Titan allowed the potential presence of liquid methane, liquid ethane or liquid propane on the surface of the Orange Moon. At the relatively significant distance of Titan and Saturn from the Sun, the energy received from our own star is particularly low so that the environmental temperature on the Opaque Moon is aroud -179 degrees Celsius, -292 degrees Fahrenheit or 94 Kelvin. The atmospheric pressure at the level of the soil is around 1,5 Bars which is higher than that at sea level on Earth. Scientists knew that the atmosphere of Titan was dominated by molecular nitrogen and that methane represented the second most abundant compound in the hazy atmosphere. That's why the hypothesis of a global ocean of hydrocarbons was put forward by many scientists.
The Cassini-Huygens spacecraft reached the Saturnian System in mid-2004. The Cassini probe was equipped with several instruments such as the Radar Mapper and the Visual and Infrared Mapping Spectrometer or VIMS. Researchers were going to be able to collect data regarding the meteorology and the surface of Titan thanks to the Radar Mapper and thanks to the infrared and near-infrared eyes of the Cassini probe in particular. As soon as 2004, the Cassini probe collected the first data regarding the surface of the Opaque Moon revealing a contrast between high-albedo areas and low-albedo areas mostly found at low latitudes. Some scientists believed that those dark areas contrasting with bright areas represented seas or oceans of liquid methane or ethane even if some specialists argued that the low-albedo regions were not dark or uniform enough to be composed of liquids.
The Cassini probe of NASA dropped the lander known as Huygens on December 24, 2004 for a 20-day journey towards the surface of the Orange Moon. The Huygens module and its atmospheric shield could be compared with a flying saucer. The Huygens probe would have to withstand the harsh conditions of Titan's atmosphere. The designers or developers of the Huygens probe proposed by the European Space Agency had anticipated several configurations regarding the touchdown including a splash into a sea or ocean of hydrocarbons. That's why the Huygens module was able to float on an hypothetical sea, lake or river. The lifespan of the Huygens probe was particularly short due to its limited level of energy. The Huygens probe couldn't count on the solar energy which is too weak at this distance for conventional solar panels. The module had to rely on nuclear energy which would fuel the living probe for a few hours once on the surface of the giant moon.
The Huygens module performed a spectacular plunge into the Titanian atmosphere acquiring key data regarding the atmosphere and the landscape. A multitude of panoramic views were obtained from the parachuted probe and transmitted to the Cassini orbiter which had to be in the right place to collect the data. The Cassini spacecraft would rapidly go down below the horizon of the Huygens probe preventing new data from coming. During the atmospheric descent, the probe managed to obtain key data regarding the environmental temperature, the density, the atmospheric pressure, wind speed, the nature of the complex organics or the nature of the haze or the dense atmosphere. From the altitude of about 45 miles or 70 kilometers, the sky became clearer and the landscape could be discerned. The probe took remarkable images of the landscape revealing a radical contrast between a dark or brownish plain resembling a sea and bright hills resembling a glacier or banquise. Researchers and the general public were fascinated by what they saw. Dark sinuous channels in the bright areas or in the hills were clearly discerned in the views. Those channels are likely drainage channels or dried-up rivers. The aerial views led some persons or scientific journalists to advance that the dark plain corresponded to a methane sea.
During the historical atmospheric descent, hundreds of images were taken with the Descent Imager/Spectral Radiometer or DISR allowing the creation of a video of the descent. The area where the Huygens probe landed probably undergoes seasonal rainfall. That's what the aerial images suggest. Methane or ethane rain can produce strong erosional processes sculpting the landscape in the same way as on Earth and can engender canyons or steep ravines. The dark channels may also correspond to fractures even if the hypothesis for drainage channels at low latitudes is favored. After the touchdown, the Huygens probe survived and collected captivating views of the soil and the horizon. Eroded stones or pebbles could be clearly discerned near the probe implying that the probe may have landed onto an ancient river.
The Cassini probe which has been collecting key data regarding the atmosphere of Titan and its landscape is still operating today but its mission is expected to come to an end on September 15, 2017 with a big plunge into Saturn's atmosphere. The Cassini team members and NASA leaders have performed an extraordinary work over the years since the big start of the Cassini-Huygens mission in the Saturnian System in 2004. Here are some comments. Linda Spilker who is Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, California advanced : « The Huygens descent and landing represented a major breakthrough in our exploration of Titan as well as the first soft landing on an outer-planet moon. It completely changed our understanding of this haze-covered ocean world.»
Carolyn Porco who is Cassini imaging team lead at Space Science Institute in Boulder, Colorado pointed out : « The Huygens images were everything our images from orbit were not. Instead of hazy, sinuous features that we could only guess were streams and drainage channels, here was incontrovertible evidence that at some point in Titan's history – and perhaps even now – there were flowing liquid hydrocarbons on the surface. Huygens' images became a Rosetta stone for helping us interpret our subsequent findings on Titan. » Since the beginning of the Cassini-Huygens mission, radar data obtained from the Cassini orbiter have clearly shown that the dark areas or low-albedo areas in the infrared or near-infrared spectrum found at low latitudes are dominated by Seif dunes or parallel and linear dunes extending over long distances and shaped by prevailing winds. As a result, one can advance the hypothesis that the low-albedo areas located at low latitudes may correspond to ancient seas.
Alex Hayes who is a Cassini scientist at Cornell University, Ithaca, New York argued : « Cassini and Huygens have shown us that Titan is an amazing world with a landscape that mimics Earth in many ways. During its descent, the Huygens probe captured views that demonstrated an entirely new dimension to that comparison and highlights that there is so much more we have yet to discover. For me, Huygens has emphasized why it is so important that we continue to explore Titan. » Researchers became aware in particular that there may be seasonal phenomena in the area such as seasonal rainfall or monsoon events. Eroded stones or pebbles identified on the surface near the probe were the proof that a stream of liquid hydrocarbons, methane, ethane or propane must have taken shape relatively recently where the probe landed.
Jim Green who is director of planetary science at NASA Headquarters in Washington advanced : « Twelve years ago, a small probe touched down on an orangish, alien world in the outer solar system, marking humankind's most distant landing to date. Studying Titan helps us tease out the potential of habitability of this tiny world and better understand the chemistry of the early Earth. » Thanks to the Radar Mapper, the infrared and near-infrared eye of the Cassini spacecraft, scientists have been in a position to obtain a relatively detailed map of Titan's surface and significant clues regarding the meteorology or the methane cycle on Titan. We know, now, that lakes, seas and rivers are found at high latitudes or in the polar regions of Titan. If we had known as soon as the start of the Saturnian journey that the pools of liquids were mostly concentrated in the high latitudes of the northern hemisphere, we would probably have sent the Huygens probe to seas or lakes like Kraken Mare, Ligeia Mare or Punga Mare. Are there huge waves as some researchers had predicted long ago ? Is there a complex organic chemistry within the pools of surface liquids dominated by hydrocarbons ? That's a major question we are eager to answer. Let's hope we'll have the answer very soon !
The image above corresponds to a panoramic view of the area where the Huygens probe landed on January 14, 2005. During its atmospheric descent, the Descent Imager/Spectral Radiometer acquired a multitude of images of its environment. This image represents a flattened (Mercator) projection of a view obtained at an altitude of 10 kilometers or 6 miles. One can notice the remarkable contrast between the dark, brownish plain and bright hills. Image Credit: ESA/NASA/JPL/University of Arizona.
The artist's impression above reveals the surface of Titan in a low-albedo area at a low latitude on Saturn's largest moon Titan. Radar images have clearly shown that the regions which appear dark and mark a clear contrast with bright areas at a low latitude are dominated by Seif dunes or linear and parallel dunes extending over long distances, influenced by prevailing winds. Winds and rainfall of methane or ethane can engender erosional processes like well-known meteorological processes occurring on Earth. Image Credit: Marc Lafferre, 2017.
- To get further information on that news, go to : https://saturn.jpl.nasa.gov/news/2987/huygens-ground-truth-from-an-alien-moon.