Signs of Water Found On Saturnian Moon Enceladus

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."

Comments

The pendulum swinging

[JoshuaZ]

In the 19th and early 20th century, the prevailing view was that life, even intelligent life, was common in the solar system. Then as time progressed, we realized how hostile most of the world is. The moon had a vacuum, liquid water was rare, Venus was hundreds of degrees too hot. Now it seems the pendulum swings in the opposite direction as we realize how common liquid water and other precursors to life are. We now have liquid water on Mars, and circumstances on multiple moons of Jupiter and Saturn that could be conducive to life. It seems pretty clear that we aren't going to find much in the way of advance life (the only possibility for it is maybe Europa, but I'm probably overestimating the probability there just out of love for 2001) but it seems more and more likely that we will find life in the solar system on bodies other than Earth. What will find from that, who knows. But I'm willing to bet that we will find such life in the next 20 years.

Re:The pendulum swinging

[Tim C]

There are creatures on earth that do not get their energy from the sun - they live near hydrothermal vents deep in the oceans. That's one possibility that we have seen ourselves; in fact it was this discovery in part that spurred on the search for life on other planets that would normally have been written off as far as supporting life was concerned.

Re:The pendulum swinging

[elysiana]

Aha, we have now obtained your true identity! You can come forward, Mr. Anonymous Coward. The game is up.

Re:The pendulum swinging

[sznupi]

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

[dissy]

Isn't distance from the sun pretty empirical, though?

Not exactly, and not really.

Any source of heat will do, the sun is just a convenient free source of it for those planets near enough, and while not technically unlimited, is close enough for our current needs and not even an issue for any society under a KT-I level (like us)

Earth's 'sweet spot' is occupied by, well, Earth, and little else. This moon of Saturn may have water, but where is it getting its replacement for solar power?

The main source of heat is the same as Earths secondary source of heat.
Left over energy from the planets (or moons) formation in the early solar system. Typically the symptoms of this are a molten semi-liquid core, and centrifugal forces imparted to it during it's creation.

Also Europa has Saturn and it's magnetic field and gravity well to generate energy.
As the moons orbits are not circular but instead elongated, this means in a single trip around it's host body, half the time it is closer to the planet than the other half (and in seasonal quarters like Earth has) which gravitationally pulls on the moons surface stronger during the closer orbit times.
This process generates a bunch of geothermal activity, motion, and heat energy from friction.
http://en.wikipedia.org/wiki/Tidal_flexing

The top layer of ice is very thick, and only the first couple meters are needed before the suns radiation are blocked enough to not be damaging to anything under that level.
Moving water (and thus food) due to tidal flexing between the liquid inner layer (be it water or whatever it happens to be) and the frozen solid crust.
A hot and mobile semi-liquid metallic core to provide heat to the lower levels that don't get much or any energy from the sun.

If it wasn't for the fact the rest of Earths ecology wasn't there, there are a number of life forms on Earth that we could drop off under the ice right now and they would have an extreamly high chance of survival (again admitting, with a support and food supply)

If life was to or has started from the basics there, the foundation of support for an ecology would be in place (at least for life that evolved there), and there is plenty of sources of energy compared to current known life forms on earth (not us, but humans are far from the life form majority on this planet)

My guess - it isn't.

While you may be correct, it would only be correct by accident :)

We have many life forms on earth that already thrive in such conditions. So we have solid proof that such a thing is possible, and there is no reason to think otherwise.
But as we know, just because something is possible, doesn't mean it has happened more than once.

Nor are there any actual arguments if there IS life there or not, only guesses.
Within the realm of possible however, it has been proven to be possible already.

Re:The pendulum swinging

[Monkeedude1212]

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

[Chris Burke]

So you're operating under the assumption that these lifeforms evolved independently from a spontaneously-generated source?

No. It is only establishing that it is possible for life to exist in such environments.

I agree it's probable that the examples on earth evolved from life that formed where solar energy was readily available. But that doesn't necessarily mean its the only possible evolutionary path, any more than our history means warm blooded live-birthing animals can only evolve in the presence of giant reptiles who get conveniently wiped out by meteors. It also doesn't mean life can begin and evolve strictly from geological energy sources... We don't really have a good model of abiogenesis, but the things we're pretty sure are at least prerequisites are water, organic compounds like amino acids, and energy.

I'm not ready to say that the source of energy must be the sun.

Re:The pendulum swinging

[Nadaka]

There is also a fairly common biological origin hypothesis that the thermo-chemical powered life found near vents was the earliest kind of life on earth and solar powered life evolved from it. This hypothesis fits our current understanding of earths early seas rather well. Though I don't think there is any way to advance it to a theory due to the near absolute lack of fossil records from that period.

Hydrocarbons?

[KDR_11k]

Does that mean oil?

I think I hear NASA's budget skyrocketing.

Re:Why would liquid water...

[garg0yle]

Have scientists been able to throw together basic ingredients of living things and have the resulting pile resemble anything even close to life? Even in perfectly favorable lab settings?

yep

(Depending on how you define "life", of course)

Re:I like enchiladas

[spun]

I like echidnas too but they're not food!

I take it you've never had echidna enchiladas. Once you pick out the spines, they're delicious.

Re:Two years to analyse the data ?!

[Convector]

I was not involved in this study, but I've published in Icarus before. It's a good journaly, but has notoriously slow publication times. If you actually look at the article, you'll see that the original submission date was Nov. 2008. It went through review and was sent back for revision. Given the time, it's likely the revision was also sent out for review. It was accepted in July 2009. It's probably been available on the website shortly after that, but because Icarus only prints a certain number of articles per issue, it's taken this long to slog through the publishing queue.