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Nearby Ocean Worlds Could Be Best Bet For Life Beyond Earth, Says NASA (cnn.com)
NASA has new evidence that the most likely places to find life beyond Earth are Jupiter's moon Europa or Saturn's moon Enceladus. In terms of potential habitability, Enceladus particularly has almost all of the key ingredients for life as we know it, researchers said. From a report: New observations of these active ocean worlds in our solar system have been captured by two NASA missions and were presented in two separate studies in an announcement at NASA HQ in Washington today. Using a mass spectrometer, the Cassini spacecraft detected an abundance of hydrogen molecules in water plumes rising from the "tiger stripe" fractures in Enceladus' icy surface. Saturn's sixth-largest moon is an ice-encased world with an ocean beneath. The researchers believe that the hydrogen originated from a hydrothermal reaction between the moon's ocean and its rocky core. If that is the case, the crucial chemical methane could be forming in the ocean as well.
It's not the proximity of another moon that produces tidal forces. Just going around Saturn is enough to produce the stresses that induce heat. We can't match the heat output in our models yet because we don't have enough data on the composition of Enceladus or the size of it's ocean(s). We can't even characterize how much heat comes from nuclear decay in our own core; we're just guessing about other planets and moons. Some of Europa's heat comes from the high radiation and strong magnetic fields in the Jupiter system, so the accuracy of your claim that it's heat matches only tidal stresses is doubtful.
On the one hand you take life too seriously, and on the other, you do not take playful existence seriously enough. Seth
It's not the proximity of another moon that produces tidal forces. Just going around Saturn is enough to produce the stresses that induce heat.
Only if the orbit is eccentric. If there aren't other moons, viscoeleastic damping circularizes the orbit until the tidal heating disappears-- it's the other moons that perturb Europa's orbit to make it slightly eccentric, giving it the tidal forces that heat it.
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