The Mars Express observations hint at greater methane concentrations over areas containing subsurface water ice. Either the geologic or biological scenario would explain this correlation. Aquifers below the ice would provide a habitat for creatures or a venue for the hydrogeochemical production of methane. Without more data, the biological and geologic possibilities appear equally likely.
A Titanic Ocean
At first glance, one might think that Titan’s methane would be easier to understand: the moon formed in the subnebula of Saturn, whose atmosphere contains huge amounts of the gas. Yet the data argue for production of methane on Titan rather than delivery of methane to Titan. The Huygens probe of the joint NASA and European Space Agency’s Cassini-Huygens Mission found no xenon or krypton in the moon’s atmosphere. Had the planetesimals that formed Titan brought methane, they would have brought these heavy noble gases as well. The absence of such gases indicates that methane most likely formed on Titan.
Therefore, the presence of methane on Titan is as mysterious as it is on Mars—in some respects more so because of its sheer quantity (5 percent by volume). A plausible source, as on Mars, is serpentinization at relatively low temperatures. Christophe Sotin of the University of Nantes in France and his colleagues have argued that Titan might sustain an underground ocean of liquid water. Dissolved ammonia, acting as an antifreeze, would help to keep it from freezing solid. In their model, the ocean is 100 kilometers underneath Titan’s surface and 300 to 400 kilometers deep. In the past, the decay of radioactive elements and the leftover heat from Titan’s formation might have melted nearly all the body’s ice—so the ocean might have extended all the way down to the rocky core.
Under those conditions, reactions between the water and the rock would have liberated hydrogen gas, which in turn would have reacted with carbon dioxide, carbon monoxide, carbon grains or other carbonaceous material—producing methane. I estimate that this process would have been capable of explaining Titan’s observed methane abundance. Once produced, methane could have been stored as a stable clathrate hydrate and released to the atmosphere either gradually, through volcanism, or in bursts, triggered by impacts.
An intriguing clue is the argon 40 gas detected by Huygens as it descended through Titan’s atmosphere. This isotope forms by the radioactive decay of potassium 40, which is sequestered in the rocks deep in Titan’s core. Because the radioactive half-life of potassium 40 is 1.3 billion years, the small amount of argon 40 in the atmosphere is evidence for slow release of gases from the interior. In addition, optical and radar images of the surface show signs of cryovolcanism—geyserlike eruptions of ammonia-water ice—which also indicates that material wells up from the interior. The surface appears relatively young and free of craters, which is a sign of resurfacing by material from the interior. The estimated resurfacing rate would release methane from the interior quickly enough to balance the photochemical loss. Methane on Titan plays the role of water on Earth, complete with liquid surface reservoirs, clouds and rain—a full-fledged methalogical cycle. Thus, a substantial body of evidence exists, even more so than for Mars, that methane stored in the interior would have no difficulty getting out to the surface and subsequently evaporating into the atmosphere.
Might biology also play a role in creating Titan’s methane? Christopher McKay of the NASA Ames Research Center and Heather Smith of the International Space University in Strasbourg, France, as well as Dirk Schulze-Makuch of Washington State University and David Grinspoon of the Denver Museum of Nature and Science, have suggested that acetylene and hydrogen could serve as nutrients for methanogens even in the extreme cold of Titan’s surface (–179 degrees C). This biogenic process differs from that employed by methanogens on Earth and their cousins, if any, on Mars in that no water is needed. Instead liquid hydrocarbons on Titan’s surface serve as the medium.
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Add CommentWant to see some real closeups of Mars,plus life like critters-take a look at these Italian 100 foot off the surface of Mars- see roots,animals footprints etc: www.msss.com/moc_gallery/e07_e12/full_glf_non_map/e10/e1001841.glf
Reply | Report Abuse | Link to thisToreityerate, I suggest staining the atmosphere with a harmless dye the is sensitive to mehane like a gram stain. Use the dye to contrast and locate the sources of methane and any sinks that may explain where the methane gas is recycled. Different optical filters can visually id the sources of methane once the atmosphee is stained.
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Reply | Report Abuse | Link to thisBrilliant!!! After you have invented such a miracle dye that can stain gases in the atmosphere, maybe you can also invent a method to move the requisite millions of tons of that stuff to Mars.
Surely there are non-biological chemical reactions in the vast sub subsrface of the earth that produce methane. The "primitive" tribes along the Alieutian Ismuth between Alaska and Kamchatka lived along the end of the "Circle of fire"that curved around what is now the southern Berring SEa, and according to their descendents folk songs and myths, they named the semi-circled arewa the Farting Sea becasuse of the smell of the undersea effusians that they tapped by ceramic turbines to "energize their first industrial revolution about 11 Millenia ago at the end of the ice age and before the great Tunguska like explosion of a comet over the Arctic Ocean around the North pole that caused the tsunamis ande earth/ice quakes that emptied the Arctic ocean across the world, much through what is now the Bering Sea, denuding of life much of what is now the outer Aleutian chain of islandsislands and some islands such as St Lawrence --and in the other direction from the North Ple, around Iceland and the Isthmus of Faroe to northern Scotland, washing away in the procesws all the evidence of the world-wide industrtialization that was created at the end of the ice age by relying on ceramic turbines utilizing the methane eruptions from the rings of fire and other undersea volcanic sources of power.
Reply | Report Abuse | Link to thisThe point is that all that volcanic methane had to come from somewhere and although we call manatees "sea cows" there just we not millions of giant sea cows farting throughout the seas whose methane wan in some way sequestered into some subsurface bubble that farted gently until perturbed by an exploding comet and its consequential quakes and shifts of a quarter of the water in the world from the Arctic ocean down across EurASIa, North America and the North Atlantic and North Pacific as well as the Bering Sea that bore the brunt of the floods, equal to those that crossed from the Black and Caspian Seas, etc, cleared out the Dardanelles and flowed over what is now Turkey, across the later "Fertile Crescent" and over Lebanon into the great Valley of Middle Earth that is now the Mediterranian sea befor it carved out the Straits ofr Gibralter, met the floods from the North Atlantic ro inundate Atlantis before rushing across the Atlantic and Carribean Islands, washing away the Isthmusfrom Florida to Cuba and proceeding to cross the Mexican Sea (now the Gulf of Mexico and dumping its debris anong the Texas coast, forming what are now barrier islands off-shore from what it had formed as the Great South Texas Salt Sea, now almost all evaporated and covered and covered bysands liberated by winds over THE Continental Shelf and circled by the cedars of Lebanon brought across the Mediterranian Sea and Atlantic Ocean, and growing as if they had been natives around the last of the 4lakes left over from the Great South Texas Salt Sea whose salt was left by evaporation under the South Texas sun as a layer about a foot thick under the sandy soil about 25 feet down.
Surely there are non-biological chemical reactions in the vast sub subsrface of the earth that produce methane. The "primitive" tribes along the Alieutian Ismuth between Alaska and Kamchatka lived along the end of the "Circle of fire"that curved around what is now the southern Berring SEa, and according to their descendents folk songs and myths, they named the semi-circled arewa the Farting Sea becasuse of the smell of the undersea effusians that they tapped by ceramic turbines to "energize their first industrial revolution about 11 Millenia ago at the end of the ice age and before the great Tunguska like explosion of a comet over the Arctic Ocean around the North pole that caused the tsunamis ande earth/ice quakes that emptied the Arctic ocean across the world, much through what is now the Bering Sea, denuding of life much of what is now the outer Aleutian chain of islandsislands and some islands such as St Lawrence --and in the other direction from the North Ple, around Iceland and the Isthmus of Faroe to northern Scotland, washing away in the procesws all the evidence of the world-wide industrtialization that was created at the end of the ice age by relying on ceramic turbines utilizing the methane eruptions from the rings of fire and other undersea volcanic sources of power.
Reply | Report Abuse | Link to thisThe point is that all that volcanic methane had to come from somewhere and although we call manatees "sea cows" there just we not millions of giant sea cows farting throughout the seas whose methane wan in some way sequestered into some subsurface bubble that farted gently until perturbed by an exploding comet and its consequential quakes and shifts of a quarter of the water in the world from the Arctic ocean down across EurASIa, North America and the North Atlantic and North Pacific as well as the Bering Sea that bore the brunt of the floods, equal to those that crossed from the Black and Caspian Seas, etc, cleared out the Dardanelles and flowed over what is now Turkey, across the later "Fertile Crescent" and over Lebanon into the great Valley of Middle Earth that is now the Mediterranian sea befor it carved out the Straits ofr Gibralter, met the floods from the North Atlantic ro inundate Atlantis before rushing across the Atlantic and Carribean Islands, washing away the Isthmusfrom Florida to Cuba and proceeding to cross the Mexican Sea (now the Gulf of Mexico and dumping its debris anong the Texas coast, forming what are now barrier islands off-shore from what it had formed as the Great South Texas Salt Sea, now almost all evaporated and covered and covered bysands liberated by winds over THE Continental Shelf and circled by the cedars of Lebanon brought across the Mediterranian Sea and Atlantic Ocean, and growing as if they had been natives around the last of the 4lakes left over from the Great South Texas Salt Sea whose salt was left by evaporation under the South Texas sun as a layer about a foot thick under the sandy soil about 25 feet down.
Sorry, I want to see them but can't see them; the link don't work!
Reply | Report Abuse | Link to thisSorry for my duplicate posts above but I didn't think it had posted because it said my log on had failed. If there is a way to delete the duplicate, please let me know.