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To: SubMareener; eyeamok
It is turning out “fossil fuel” is a misnomer. We are recovering oil from depths that never saw a dinosaur footprint or a big fern. This stuff is made in the mantle from raw materials that we can’t possibly exhaust.

For what it’s worth...

The Mystery of Methane on Mars and Titan

It might mean life, it might mean unusual geologic activity; whichever it is, the presence of methane in the atmospheres of Mars and Titan is one of the most tantalizing puzzles in our solar system

Of all the planets in the solar system other than Earth, Mars has arguably the greatest potential for life, either extinct or extant. It resembles Earth in so many ways: its formation process, its early climate history, its reservoirs of water, its volcanoes and other geologic processes. Microorganisms would fit right in. Another planetary body, Saturn’s largest moon Titan, also routinely comes up in discussions of extraterrestrial biology. In its primordial past, Titan possessed conditions conducive to the formation of molecular precursors of life, and some scientists believe it may have been alive then and might even be alive now.

To add intrigue to these possibilities, astronomers studying both these worlds have detected a gas that is often associated with living things: methane. It exists in small but significant quantities on Mars, and Titan is literally awash with it. A biological source is at least as plausible as a geologic one, for Mars if not for ­Titan. Either explanation would be fascinating in its own way, revealing either that we are not alone in the universe or that both Mars and Titan harbor large underground bodies of water together with unexpected levels of geochemical activity. Understanding the origin and fate of methane on these bodies will provide crucial clues to the processes that shape the formation, evolution and habitability of terrestrial worlds in this solar system and possibly in others.

Methane (CH4) is abundant on the giant planets—Jupiter, Saturn, Uranus and Neptune—where it was the product of chemical processing of primordial solar nebula material. On Earth, though, methane is special. Of the 1,750 parts per billion by volume (ppbv) of methane in Earth’s atmosphere, 90 to 95 percent is biological in origin. Grass-eating ungulates such as cows, goats and yaks belch out one fifth of the annual global methane release; the gas is a metabolic by-product of the bacteria in their guts. Other significant sources include ­termites, rice paddies, swamps, leakage of natural gas (itself a result of past life) and photosynthetic plants [see “Methane, Plants and Climate Change,” by Frank Keppler and Thomas Röckmann; Scientific American, February 2007].

Volcanoes contribute less than 0.2 percent of the total methane budget on Earth, and even they may simply be venting methane produced by organisms in the past. Abiotic sources such as industrial processes are comparatively minor. Thus, detection of methane on another Earth-like object naturally raises the prospect of life on that body.

In the Air
That is what happened with Mars in 2003 and 2004, when three independent groups of scientists announced the discovery of methane in the atmosphere of that planet. Using a high-resolution spectrograph at the Infrared Telescope Facility in Hawaii and at the Gemini South Telescope in Chile, a team led by Michael Mumma of the NASA Goddard Space Flight Center detected methane concentrations in excess of 250 ppbv, varying over the planet and perhaps over time.

Vittorio Formisano of the Institute of Physics and Interplanetary Science in Rome and his colleagues (including me) analyzed thousands of infrared spectra collected by the Mars Express orbiter. We found methane to be much less abundant, ranging from zero to about 35 ppbv, with a planetary average of approximately 10 ppbv. Finally, Vladimir Krasnopolsky of the Catholic University of America and his colleagues, using the Canada-France-Hawaii Telescope, measured a planetary average of about 10 ppbv. They could not determine the variation over the planet because of poor signal and spatial resolution.

Mumma’s team is now reanalyzing its data to try to determine why its value is the outlier. For now, I will take the 10 ppbv value as the most likely. It corresponds to a concen­tration of methane (in molecules per unit volume) that is only 40 millionths of the concentration in Earth’s atmosphere. Nevertheless, even the barest presence of the gas demands an explanation.

Although astronomers detected methane on Titan as early as 1944, it was only the additional discovery of nitrogen 36 years later that generated the immense interest in this cold and distant moon [see “Titan,” by Tobias Owen; Scientific American, February 1982]. Nitrogen is a key constituent of biological molecules such as amino acids and nucleic acids. A body with a nitrogen-methane atmosphere, where the ground-level pressure is one and a half times that of our home planet, may have the right ingredients for molecular precursors of life and, some have speculated, even life itself to form.

Methane plays a central, controlling role in maintaining Titan’s thick nitrogen atmosphere. It is the source of hydrocarbon hazes, which absorb solar infrared radiation and warm the stratosphere by approximately 100 degrees Celsius, and of hydrogen, whose molecular collisions result in a 20-degree warming in the troposphere. If the methane ever ran out, temperatures would drop, nitrogen gas would condense into liquid droplets and the atmosphere would collapse. Titan’s special character would change forever. Its smog and clouds would dissipate. The methane rain that seems to have carved its surface would stop. Lakes, puddles and streams would dry up. And, with its veil lifted, Titan’s stark surface would lay bare and readily accessible to telescopes on Earth. Titan would lose its mystique and turn into just another satellite with thin air.

could it be that methane on Mars and Titan has a biological origin, as on Earth, or does it have another explanation, such as volcanoes or impacts of comets and meteorites? Our understanding of geophysical, chemical and biological processes has helped narrow the field of possible sources on Mars, and many of the same arguments apply to Titan as well. ...”

continued...

https://www.scientificamerican.com/article/methane-on-mars-titan/

39 posted on 02/09/2017 8:45:58 AM PST by ETL (Trump admin apparently playing "good cop, bad cop" with thug Putin (see my FR Home page))
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To: ETL

Or there isn’t any life on those places and this is abiogenic methane.


42 posted on 02/09/2017 8:47:56 AM PST by HiTech RedNeck (Embrace the Lion of Judah and He will roar for you and teach you to roar too. See my page.)
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