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Oceans Potentially More Common In Solar System
nairolF writes "The AIP Physics News Update has a brief note on how water oceans might be more common in the solar system than previously thought, rendering useless the old notion of a narrow "habitable zone" in solar systems, outside of which life cannot exist."
Why are we spending all our time trying to protect ours? Let's waste it like rock stars in a holiday inn!
tcd004
Janet Reno Margolis for Florida Gov.
Here's an interesting paper on the same subject and by the same professor that spoke at the conference. You can find it in .pdf on his caltech homepage.
True warriors use the Klingon Google
Oceans are believed essential for life, but so was the habitable zone. It is the height of "optimism" to believe that if one is wrong, the other must be even more right than before.
There is life on Earth which exists in deep, oceanic trenches, near hot volcanic vents. Since that life could not exist prior to the volcanic vent opening, it can be assumed that the formation of life, at it's most basic, is occuring on a regular basis. These life-forms may or may not have any nucleic structures we would recognise.
For this reason, until such extreme life-forms on Earth are better understood, and the range of conditions in which they can form are better quantified, only the very brave, or very stupid, could claim that "factor X will make life more/less abundant in our Universe". All we really know is that the picture is a hell of a lot more complicated than it used to be.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Here's an interesting point: When people talk about whether water would be liquid or solid on mars, they're referring to pure, 100% distilled water, not brine or any water with salts in it. When there are dissolved substances, the freezing point is depressed, so water could be -10 C during the day and still liquid.
Also, on Earth, there is a plethora of water below the surface, although you would not want to drink it. It's usually saturated in salts like calcium or sodium chloride, carbonates, and sulfates. However, even 10 km below the surface of the Earth, in hot conditions and high pressures, 0bacteria thrive in these conditions (as they do in the Hydrocarbon deposits as well).
Given that Mars has plenty of surface evidence of (geologically) recent free flowing water, the scientific community would be remiss to assume that subsurface water does not exist. It likely has a lot of brine belows it's surface, perhaps rich in Iron salts.
Also, there are moons of Jupiter, like Europa (which is basically 10 km of ocean from what we can see on the surface) and Ganymede (with a lot of hydrocarbons) where conditions that bacteria and simple one celled life require exist. Given that we have already learned that bacteria in hostile environments on Earth (Antarctica, for example, in very dry and cold conditions) can hibernate for millions of years, it's conceivable that rocks knocked loose from Earth from the occasional large meteor (i.e. asteroid or comet) could transport bacteria to Mars and elsewhere. I think that if life did not evole there, it was transported from Earth by this process (or perhaps even the other way). Some people have speculated that bacterial or similar life found on Mars or elsewhere within this solar system is completely different from that found on Earth -- I would postulate that it is probably no more 'alien' that what we might find in the ocean near black smokers, that big underice lake in Antarctica (can't remember the name), or a barren, cold, high altitude mountain.
---this is not your kill9 sig
Do you have a better indicator for life than water? What chemical should we be looking for? Researchers don't believe that water is absolutely necessary for life. But is sure has facilitated our kind of life, and that is the only kind of life we know. So where should we start looking for extraterrestial life? In places with lots of silicon? Not likely. Where there is water seems to be a good place to start. And that thing about discovering life and probably not recognizing it is bunk. The chances are actually very slim that we could'nt recognize it. Sure, we might think it's some sort of funny chemical reaction that needs investigation at first. But as soon as we know that there is reproduction with information being passed on, we know that it is life.
The statements is not incorrect. The implication you take from it is incorrect. "If A then B" does not logically imply "If not-A then not-B".
(Though it is a fairly common mistake, so it could be argued that science writers might want to take it into account when they write their articles.)
Ok, I'm going to be the crotchety scientist, you'll have to forgive me.
Ok, lets get some things straight. There's evidence that liquid water can exist in places outside our old 'habitable zone'. We know that organisms can thrive in boiling and subzeo (but still liquid) water, as well as surviving frozen inside ice (as happens annually in the ice shelves of antarctica).
So, this means that its *possible* for life as we know it to exist in these extraterrestrial oceans. No one is saying its there, just that its worth a look. Likewise, no one has proven that life can't exist without water. However, the only kind of life we *know* exists, does require water, and is carbon-based. I hope someday that we find that life exceeds this "narrow" category, but since we'd first just like to find any life at all, where do you think we're going to look? For the moment, time, energy, and resources are most likely to give results if we apply them according to our best information about life, however meager.
Rant over. Now get the hell off my lawn you kids!
Entropy gets everyone.
Organic chemistry as we know it, that is simple acid molecules grouping into proteins and with carbohydrates, requires not just water and quite a lot of it. Although ammonia will also provide a media for these chemical structures, there are other requirements which may limit the ability of all but a small number of oceans from supporting life. Note that the three extreme conditions on Earth normally considered (dry cold of Antarctica, near freezing and crushing pressures of ocean depths and undersea vents) all did not develop their own life, but provided suitable environments for existing life to adapt to. Could any other planetoid in the solar system support life? Possibly. Develop it independently? Very, very much less likely.
So long and thanks for all the fish . . . !!!