Signs of Water Found On Saturnian Moon Enceladus 79
Matt_dk writes "Scientists working on the Cassini space mission have found negatively charged water ions in the ice plume of Enceladus. Their findings, based on analysis from data taken in plume fly-throughs in 2008 and reported in the journal Icarus, provide evidence for the presence of liquid water, which suggests the ingredients for life inside the icy moon. The Cassini plasma spectrometer, used to gather this data, also found other species of negatively charged ions including hydrocarbons."
Re:The pendulum swinging (Score:2, Interesting)
Who knows if there aren't types of life that can subsist on the reduced solar power over there. There's also the option of volcanic activity feeding heat into the ecosystem but I think volcanic activity is fairly rare.
Re:The pendulum swinging (Score:1, Interesting)
Aren't there bacteria that live off of solar power? If so if there is enough heat to keep water in its liquid state, there might be enough power to at least energize simple singe cell-type organisms (which I feel is the most probabilistic life forms to find in this solar system).
Re:The pendulum swinging (Score:4, Interesting)
Life needs energy, sure, but that doesn't mean the energy has to be in the form of solar light. Some of Solar System moons get quite a lot of energy by tidal heating; for an extreme example, see Io.
What I wonder is how plausible would be to get Cassini back through Interplanetary Transport Network (low energy routes throughout our system). In the future Cassini power will diminish to a point where it will be hard to keep experiment packages alife. But perhaps there would be just enough propellant by then to direct it back through ITN? Just enough power to keep main systems alive for few decades? Bring it closer to us, so in 50 years or so we can examine it easily. Perhaps something hatched on for the ride while Cassini was flying through plumes from Enceladus in orbit around Saturn...
Re:The pendulum swinging (Score:4, Interesting)
I don't think either of you are qualified to make that assertation. A year of Bio/Physical Anthropology for extra credit is not enough.
You need to explain why its more likely that they adapted from solar sourced ancestors as opposed to thermal heat vents. I think that form of adaptation would be quite rare, as evolution takes a long time. And you can't expect a solar sourced species to survive in a non-solar environment very long.
Re:The pendulum swinging (Score:1, Interesting)
A dude at NASA (David McKay) believes he will be able to conclusively present evidence that Martian meteorites on Earth contains fossils of Martian bacteria (past life) before the end of this year. His findings were first announced in a televised message by president Bill Clinton in 1996, but they have remained fairly controversial until now. This year, his team have been given funding to conduct new analyses using much more sophisticated instrumentation that were available in 1996 - and he is convinced the results will be positive and very difficult to challenge.
Exciting times.
Re:The pendulum swinging (Score:3, Interesting)
but it seems more and more likely that we will find life in the solar system on bodies other than Earth.
I'm not sure how likely it is. We might find life elsewhere in the solar system, but it's also quite possible we won't.
However at the very least what all of the data we're collecting suggests is that liquid water, hydrocarbons and other organic chemicals, the things we associate with the chemical requirements for life, are not actually uncommon. So even if it requires an earth-like planet both in composition and in relative distance from the parent star, we can be confident that the composition itself is not rare, and based on how swimmingly well the search for exoplanets is going*, I think we can say that the odds of there being earth-like planets with liquid water and hydrocarbons and all that around other stars is high.
So, maybe not in our solar system, but I'm putting down the odds of there being life "out there" as being pretty damn good.
* Basically, every type of planet we have the capability of discovering, we discover. First huge gas giants really close to the star, then gas giants farther out, rocky planets of several earth masses very close to the star... Every time our capabilities improve, we readily find planets that only the new capabilities would show.
Re:The pendulum swinging (Score:3, Interesting)
There's probably other variations out there that can provide an energy source, things much harder, and thus never took off on Earth where energy was easy. I fully expect we'll end up finding life a lot more frequently than we expect at the moment. It'll mostly be stuff we can't have conversations with though.
There's also the whole thing about asteroids carrying life from one place to another. Just because it's hard for life to arise in a particular place in a solar system doesn't mean it can't get transported elsewhere and evolve to thrive, or at least survive.
Re:The pendulum swinging (Score:3, Interesting)
Radiation can fuel life also. http://www.washingtonpost.com/wp-dyn/content/article/2006/10/19/AR2006101901671.html [washingtonpost.com]
Re:The pendulum swinging (Score:2, Interesting)
As an example, it's easy to engineer proteins that are either much more stable or much less stable than the ones typically found in Earth organisms. Our proteins have evolved to be exactly as stable as they need to be in order to work well under physiological conditions. Heat them up a bit and they denature. Cool them down and they stop working. But if Earth were much warmer or much colder, our proteins would just have evolved to be much more (or less) stable, and then they would work nicely under those conditions.
And then there's the question of very different chemistries. Could life exist at 2000 Celsius? Certainly not life as we know it, since our biological molecules would all be vaporized. But there are other materials that are solid on Earth, but would become soft and reactive at those temperatures. Could life be formed from them? We just don't know.
Re:The pendulum swinging (Score:3, Interesting)
Probably the same place that Europa and Io are around Jupiter, massive tidal forces. Alright, in Io's case it's even cooler, because it's proximity to Jupiter's magnetosphere creates all kinds of extra energy.
You forget these moons aren't orbiting a relatively inert body like Earth, which produces very little radiation and gravitational energy of its own. We're talking about massive gas giants who exert extraordinary tidal forces on bodies orbiting them. Tidal forces mean churning of the core, which means geological activity which means heat, which means the water is liquefied. There's no lack of energy around either Saturn or Jupiter.
Re:Two years to analyse the data ?! (Score:4, Interesting)
wow (Score:2, Interesting)