In his 1992 book Steps Toward Life, Nobel Prize winner and Director of the Max Planck Institute, Manfred Eigen, focuses on the origins of life. He introduces the theme of the book by saying that no information can arise in thermodynamic equilibrium.
He explains that equilibrium is a stable state where entropy is at a minimum. Therefore, “no perturbation” means that there will be no change in the probability distribution of a system.
For us, interested in how life began, it means that things have to be shaken up thermally for new forms of activity to arise and evolve. Our best chances of finding life somewhere beyond Earth are in places subject to continual thermodynamic change, places with a temperature change going in all the time.
The geysers on the south end of Saturn’s moon, icy Enceladus, suggest such changing conditions. Other hydrothermically active places could be the surface faults and melting that erases craters or Titan’s reddish clouds of organic “smog” as it mixes with methane snow. Also ever changing are the fast rotation of Saturn’s swirling clouds and the outward flow of its hot outer magnetospheric plasma. More likely are changing surface features, like Tethys long expansion trench or craters erased from Dione by fresh ice flows.
Of course, too much intense change could make the emergence of life unlikely, like Saturn’s colorful cloud decks and jet streams, driven by giant spinning storms, reaching up to 110 miles per hour.
Changing conditions for emergent life are most likely found near hot rocky interiors of moons or planets that house under-ice oceans. A warm ocean floor or ceiling might be hospitable. Hydrothermal vents could be possible, like those on Earth. Jupiter’s moon Europa might have such an ocean under ice several kilometers thick. That ice does crack and shift, and salty water does come up through the cracks, but it is hard to imagine sustained hydrothermal shifts near such a surface.
More likely possibilities for life on surfaces of cold moons or planets would be near volcanoes. Titan has volcanoes that spew water ice. Ganymede has lava flows, and Io’s volcanoes are famous. Volcanoes on Venus don’t help our life cause, since its temperature of 470oC is so high. Its only chance for housing life seems to be in the clouds, if temperatures fluctuate at friendly levels.
Io is heated by enormous gravity tides between Jupiter and its other moons. Tidal heat is also found on Enceladus along with high temperatures near the Tiger Stripes, fissures leaking at the south pole.
Neptune also squeezes its moon Triton to produce internal heat.
Frequent meteor strikes may not provide the constant thermal changes needed by life over long periods of time. No doubt they provide momentary sources of heat, but only Callisto shows a significant number of impacts of all sizes. On other moons, craters have been leveled by upwelling water freezing on the surface. Doesn’t sound too likely tome.
Another source of heat might be charged particles accelerated by planets’ magnetic fields. Jupiter comes to mind. The particles react with water to produce hydrogen and oxygen. Organics are also found.
Mars is still a puzzle, but its earlier, watery age might have kick-started life, which then left that drying planet to travel to Earth, where conditions were now dry enough and more amendable to long
Here the extremeophiles have much to teach us. They make some of these options seem possible.
Author of The Webs of Varok
Nautilus silver award 2013 YA
ForeWord finalist 2012 adult SF
Books, On Writing, Characters and More– http://ArchivesofVarok.com
Book Reviews– http://www.goodreads.com/Cary_Neeper
Animal Sentience– http://www.ladailypost.com
Complexity, Bio, Biblio and Links– http://caryneeper.com