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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."
At 5 degrees kelvin. Hardly bikini weather!
Due to the theory that under the ice of Europa is a giant ocean, NASA's JPL is talking about a mission to crack the ice open and search for biology.
Shameless journal plug? Not really, just an article the was rejected...
Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
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
Knowing that there's a large and ready source of water, which conveniently can be broken down into oxygen and hydrogen, once we get a decent portable power supply (fusion maybe?).
This may make the Jovian and Saturnian satellites the prime real estate (aside from Earth) in the Solar System (whoa, echoes of Larry Nivem) Who needs the dry, dusty Moon or Mars.
Of course, all bets are off if life is discovered on Titan or Ganymede. Greenpeace would probably start a petition to leave the environment alone, so the single celled organisms can prosper while humanity suffers on an increasingly overpopulated Earth. Then again, if it's the Chinese that get their first, well, we know how what they did to the Three Rivers Gorge, goodbye extraterrestial life, hello New Gangzhou!
I don't like the attitude of "Well, if there's water, there can be life!" That implies that people think that without water, there is no life.
Just because the life forms we know about need water to live doesn't mean that any life that may or may not be in the rest of the universe needs water.
I mean, really, can we assume that all life in the universe is carbon-based and needs water to live? I don't think so. It's entirely likely that if we were to discover life, we wouldn't actually recognize it as such.
Just my random thoughts.
Well, they've known about microbes in varying climates for a while. What I'm more curious about is non-H20 based life. Has anyone made any postulations about such life?
It strikes me as rather narcissistic to believe that the definition of life is somehow rooted to the way things worked out on this planet...
Can anyone think of any other substances that behave as dynamically as water in different temperature ranges?
People, people, people: based on what we know about life what you say is fairly true. However, it is what we don't know about how life is formed and in what forms it may take that will be clincher in discovering life other than our own. We know that for life to exist in a form that we know it, we need conditions that are similar to what we find on earth. However, there is no evidence to support a conclusive claim that life cannot exist in environments that are dissimilar from where we exist. Life may very well exist on mars, but it may be in a form we have yet to discover. Scientist are always looking for water as signs to point to the possibility for life elsewhere. Maybe there is another ideal chemical combination that may also harvest life.
"I can't argue that I'm not an idiot." - Jon Katz
$6.21 is the number of the beast before sales tax. Meh.
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)
This sounds like wishful thinking and all, but who actually believes anything can live in the environs mentioned in the story?
The article:
""Oceans might be common and diverse in our solar system and in other solar systems, according to David Stevenson of Caltech, who regards the old notion of a narrow "habitable zone" (Venus too hot, Mars too cold, Earth just right) for liquid water oceans as erroneous.
Stevenson spoke earlier this week in San Francisco at a meeting of the American Geophysical Union at a session intended to bring together two scientific communities that scrutinize very different realms--the planets and the seafloor on Earth.
The connection? Observations from the bottom of the ocean show that microbes thrive both in near-freezing seawater and in near-boiling effusions from thermal vents. These conditions might turn up in many other planetary environments.
For example, the Galileo spacecraft has provided evidence for watery oceans on three of Jupiter's moons-Callisto, Ganymede, and Europa. Subsurface oceans could be kept liquid by warmth from tidal forces (Jove wringing its satellites) or from radioactivity. Torrance Johnson of JPL, also speaking that the meeting, said that Europa's ocean might be 75-150 km thick and could thus harbor twice the water in Earth's oceans.
Stevenson added that observations also hint at oceans on Titan, Triton, and Pluto. In the case of Titan (soon to get the Galileo treatment when the Cassini spacecraft reaches Saturn in 2004) an ocean would be a mixture of water and ammonia (acting as antifreeze). Under some circumstances water might even be found inside Uranus and Neptune.""
Europa does have very likely evidence of a liquid ocean, but the article then uses that to 'assume' of living creatures there (bac). How can there be? Complex nucleotides and a slurry of other complex chemicals are required for 'life' to occur. Another problem is energy entering/leaving the system. The Earth is quite close to the sun, but europa can rely on nearly 0 energy from the sun (at least as useful radiation). Tidal energy is energy none the less, but it's too limited, even coming from Jupiter.
Energy, yes but useful, no.
Josh Crawley
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
... and how common they are. It has to do with the common belief that for an ocean to be hospitable, it needs to be within a certain threshold. They've basically taken evidence that microbes thrive in near boiling water and near frozen water, and apply that to the other suspected oceanic environments in the solar system. This says nothing about the environment required to form life however. Overall, nothing new here....
Pluto Planet Power... MAKE UP!
Remember that Charon, Pluto's moon/co Planet is close to half of Pluto's mass. The tidal force they exert on each other is significant... probably enough to keep water liquid (warm enough to support life? I dunno 'bout that) near Pluto's center.
This is, of course, assuming that Pluto is mostly made of cometary ice, rather than rock, which a lot of cosmologists think is the case.
Astrophysicists please correct me on the details.
Dead Scream...
The next Slashdot story will be ready soon, but subscribers can beat the rush and slashdot the links early!
Which begs the question. What is intelligence, and would we recognize an intellect based on completely different life experience from our own?
Hell, if consciousness is just a byproduct of a complex system, we would never know it because there would be no way to relate to such a system. I wouldn't be surprised to learn that there is some kind of life sharing the same planet with us that we never noticed because it functions on a completely different level.
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.
OK, so my knowledge of these matters comes mostly from articles on \. and discovery channel programming, and I'm not an expert, but I don't think this statement is exactly right:
rendering useless the old notion of a narrow "habitable zone" in solar systems, outside of which life cannot exist.
From my limited information on this subject, I've understood that the habitable zone is used in the context of planet forming and that the reason behind certain planets having certain compositions is their position in the solar system, mainly distance from the sun, while they were forming. Therefore the habitable zone is the area where if a planet forms there it will likely have the characteristics of a planet capable of sustaining life as we know it. The article suggests that the habitable zone only refers to an area that can sustain life now that all the planets are here, which is really only descriptive of human life and not other, unknown organisms (or possibly known like the microorganisms discussed in the article.)
~ now you know
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 . . . !!!
Gee, you finally noticed us just by thinking! And we thought we were going to have to wait for you to improve your neutrino detection!
Greetings!
The "Others"
Liberty uber alles.