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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."
A whole new stretch of ocean-front property to buy from shady realtors! They need somewhere, now that all that Louisiana swampland is finally sold.
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!
Well, why don't we go out looking for them ;-)
If it's that much more likely to find a place to live, then I'll just be wishing that much more for a mission to go out and find them. Put enough people on a big enough ship and eventually maybe they'll get there. Maybe not in their lifetime, but I'm sure they'll be able to figure out what to do.
-Space for rent
Stevenson added that observations also hint at oceans on Titan, Triton, and Pluto.
And I always thought Pluto was just a big frozen asteroid. Does it have enough mass to keep water? This seems like a typo to me. (Unless frozen water now counts as an ocean.)
--- -- - -
Give me LIBERTY, or give me a check.
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.
Number 569 #2, December 14, 2001 by Phil Schewe, James Riordon, and Ben Stein
Oceans Might Be Common and Diverse
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.
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.
the solar system
is there an understood, universal solarsystem that is now named "The Solar System"?
Surfing on Venus anyone?
Under some circumstances water might even be found inside Uranus...
Old news, the Kaopectate people have known that for years"Good things don't end with eum, they end with mania or teria." - H. Simpson
Bottled Maine spring water not exclusive enough for you?
Try new "nector of the gods" water, bottled straight from the oceans of Saturns's Moon Titan!
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....
Of course if you meant non H2O life, that is an entirely different story. My own expert opinion is that we would not recognize any such life form unless it was intelligent. And even then we would be likely to think of it as some form of machine rather than something actually living.(Paranoid crackpots like Stephen Hawking do speak of machine life - but only as an extension of our own creations)
You either believe in rational thought or you don't
Haven't you ever seen that picture of that naked chick in a clam? She was from Venus! I say we ship all of the old men to Venus so they can sun-bathe nude there! I know we'll be sacrificing that hot woman in a clam but at least we'd have the security of knowing that us geeks can once again roam the nude beaches! (with our 500x optical zoom camcorders, of course)
Think outside the globe people...
(/local/home/curiosity)-#who -u|grep thecat|cut -c 44-49|xargs kill -9
They said there might be water in Uranus.
I thought the idea of "habitable zones" had been shown to be BS ages ago. There's life in lightless boiling (well, it would be at normal pressure) water around volcanic vents. There's life under polar ice caps. Little one-celled critters can survive in space. What the heck does water have to do with blowing the "habitable zones" theories out of the water?
Scientists (and probably the media covering them) have had a habit of making such absolute statements as these for centuries. Recall the common theories of the universe around the time of Gallileo and Copernicus?
Isn't it about time scientists and those who report their findings wake up to the fact that what we know today is only what we know today, and that things might be diferent tomorrow? Report the findings, sure, but make sure your language shows that we are still looking for more information, still finding new things every day...
Little girls, like butterflies, need no excuse. -- L. Long
The world is a Ocean planet! Stange aqua aleins invade earth!
"Under some circumstances water might even be found inside Uranus..."
no shit
Your point is perfectly valid, but I think, for the purposes of narrowing the search, we must start with what we know - what we observe around us right now.
I used to hold the belief that life could possibly form in all manner of environments...
Until it occurred to me that, right here in our own solar system, there are all manner of environments right under our noses. And so far as we can see (which is not that much, admittedly), there is no life on any other planet than Earth.
In fact, even within the narrow range of environments on Earth, we can observe a gigantic difference in the quantity and diversity of life between, say, a tropical rainforest and an arctic desert.
Much as I would like to believe that life can spring up in all kinds of envrionments, the evidence we've seen so far doesn't seem to support it. In my (very uneducated) opinion, it really does look like the warm and wet climate is best for life.
Accountability on the heads of the powerful.
Power in the hands of the accountable.
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.
...outside of which life cannot exist.
:)
should read "...outside of which life as we know it cannot exist."
It really bothers me when people leave that part out. Though we haven't found any evidence yet, living organisms in other solar systems may very well have adapted to a completely different kind of environment than we have here on Earth. Just because we don't know about it or understand it yet doesn't necessarily mean it doesn't exist.
--SONET
Any fool can criticize, condemn and complain and most fools do. --Benjamin Franklin
That range is called the Goldie Locks range. Not too hot, not too cold....
they would have known about the extraterrestrial oceans. 6000 years ago, the Sumerians called Uranus and Neptune "the watery twins," and their star charts showed Pluto, which supposedly wasn't discovered until 1936. Ah, the advances of modern science...
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
Take off no Zigs there.
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 . . . !!!
Not that I'm an expert in exobiology but ammonia does meet your conditions. It does have a very different liquid temperature range, but it is nearly as light, also slightly polar, top 10 and capable of creating similiar solutions and suspensions as water.
So long and thanks for all the fish . . . !!!
The article said that there is water in Uranus. Wow.
Too true. Considering the weight of the molecule, it weights either 17g/mol or 18 g/mol. This weight change is an effect of ammonia being in presence of water: NH3 or (aq)[NH4]- . Tempature range is a moot point _AS_LONG_ as the environment has the acceptable liquid tempature. What interests me the most is what the ammonia does to biological reation with water. It'd be fun to work out the chemistry with that instead.
Josh Crawley
although i don't personally believe that there is life anywhere else, your point is a very good one. if hypothetically there was other life out there, there could be other kinds of life than just carbonical life. what about a planet full of silicon, according to evolutionists life on earth started when lightning hit some pond and chemicals just sort of made life by accident, couldn't we also say that lightning strikes on the silicon planet could make active CPUs by accident as well. yes i know this is a silly example but the odds are about the same (1 in 10e233 or thereabouts.)
anyway like i said i don't beleive any of this but it could be interesting fadder for people who write scifi novels!!
Under some circumstances water might even be found inside Uranus...
dr weiner.
Good point.
Ever read Fred Hoyle's "The Black Cloud"? Besides being the best science fiction I've ever read, it contains a highly interesting life-form, which, despite it's MASSIVE intelligence, had never thought of the possibility that there might life on planets...
"...Look on my works, ye mighty, and despair!"
Complex organisms are a product of their environment, literally. You know... evolution? By seeking for life only on planets with conditions similar to ours, are we not merely trying to find a puzzle that fits our pieces? We need water, we need certain temperatures, etc, because we evolved to fit into that environment. Life on another planet would evolve to fit conditions on that planet, it would not try to evolve to fit conditions suitable for earth organisms. :)
I believe that if we find life beyond earth, it will very likely exist in a different environment and function on different chemical principles using different biological mechanisms than we have ever encountered.
Now if you're looking for a planet to move to... that's different.
1: H2O is quite light. It's only 18g/mol. There's no other combination _I_ can think of that would be as light, as we humans are made
up of a lot of water.
Water is light, but it is dense (1.) Most organic solvents are density roughly 2/3rds, although they are more compressable than water (so they'd be roughly density 1 under high enough pressure.) Water's gross physical properties (density, viscocity and so forth) are important for a multicellular organism but, actually, if you were just a single alien cell, might not matter.
2: H2O is slightly polar, so it 'sticks' to certain structures a little more. Oil would be an interesting substitute to water, but oil is
large polimer chains. Too hard to create. However Ions would disrupt other chemicals. Also, Ions require water to have charge.
Ions require something polar (alcohol would do) to pair with, or they won't disaccoiate with their counterion. It need not be water - it could be alcohol, or it could be something exotic like liquid SH2. Atoms heavier than sulfur or iodine are insuffiently electronegative to hold much of a negative charge in a polar bond, so probably wouldn't be suitable.
The real problem is that your non-water based cell needs some way to seperate itself from the environment. If you're willing to call any self-replicating molecule "life," this may not be a requirement, but if you're looking for anything that's at least a recognisable organism, even if microscopic, this is a hard requirement to fill without water (or HI or H2S.)
The way cell membranes work is they have an oily portion (the membrane) with ionic stuff on the inside and the outside. So, you have a little bubble of water (the cell) wrapped in the oily membrane which is much like a soap bubble.
Now, in an oily solvent, at the right temperature, you might be able to have the reverse - like a hollow bubble of water floating in liquid soap. However, the forces that push small amounts of something polar out of a non-polar solute are MUCH WEAKER than the forces that push something oily out of water. This results not from an energetic effect, but from an entropic effect:
Water in a solvent state is fairly disordered, capable of forming H-bonds with different waters on all sides of it, and of tumbling around and forming different H-bonds. If you introduce a big oil molecule into the water, there are a number of positions that the water can't tumble into (people describe this as a crystal-like cage but that is inaccurate) so the water molecule becomes more ordered. This increase in order is extremely unfavorable, so all of the oily molecules are pushed out of contact with the water and into oil droplets; like when you mix oil and vinegar together.
The above is called the "hydrophobic effect" and it is the basis of how cells form embranes AND of how proteins become structured. It is pretty much the basis of all life. A similar effect does NOT occur with oily solvents! In fact, it doesn't much occur with ethanol; as far as I know, only other molecules which are much like water show this property.
3: Most of all biological elements are within the top 10 elements on the peridic chart. The reason these are used is because nuclear
fusion within the sun allows these to be made with much greater abundance. This reason also coves why no Earthen creatures use
silicon instead of carbon.
Sorry, that's not true. The earth has more iron atoms on it than carbon atoms, and scads every element through 44 (Nickel). What you say IS true for the outer planets, which didn't have their light elements significantly blasted off by some kind of solar event. Alien planets, which got their heavy elements from different supernovae (that's where heavy elements come from) might have mercury and gold in abundance as well. We don't know.
4: If you can accept the above examples of why water is better than other mostly inert transfer chemicals, then tempature also
comes into play. I know of no animals that use solid or gaseous blood. All use liquid of some type, just because diffusion (or in
water, osmosis) is easier to transport chemicals. The tempature of water being a liquid is between 255K and 310K , so most planets
are eliminated just because of the tempature needs strict control.
I cannot see life arising in solid state, because if the molecules can't move, you can't do the kind of complex molecular recognition chemistry that we understand as life.
In a gaseous state, same problem for reverse reasons - the molecules can't find each other.
That said, you can have pockets of liquid water (underground, say, or under higher pressure) at much higher temperatures. Other molecules with many of the properties of water (possibly enough) could be liquid at much lower temperatures. There is an outside chance that much larger molecules might be suitable and liquid at higher temperatures.
Really exotic solvents - like molten table salt - require temperatures so high that processes dependent on a high degree of order (like life) could never arise.
Another big problem is that complex organic solvents (polybenzenes and such) do not arise spontaneously, while water and amino acids do.
Long story short - a few very water like solvents, like HCl, H2S or HI - might substitute for water and might extend the range of allowable temperatures somewhat. However, nonpolar solvents for life, and silicon based life, appear impossible.
The one thing that is important to remember in determining viability zones is that all of the planets and some of the moons give off their own nuclear heat from fission; especially the earth and other seismically active bodies like Io. This nuclear heat might substitute for solar heat for bodies well outside of the range of their primary's warmth; especially if these alien planets were formed in much closer proximity to a supernova.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
That is an easy one.
They will want to talk our ears off, or eat our livers.
Alternatively, they may desire to stop us from eating their liver-equivalents.
I'm oversimplifying of course, but if there is no interaction between ourselves and "other" intelligence, then there may as well be no "other". Ditto for the hypothetical silicon based lifeforms of Aldebaran IV (or Anderson DD) regardless of their intellectual accomplishments.
You either believe in rational thought or you don't
Last I heard, Mars was indeed in the habitable zone. In fact, habitable zone started just a bit inside earth's orbit (and I suspect that was because arguing erath is NOT in the habitable zone would be a bit far off) and extended up until halfway between mars and asteroid belt. Did they update the definition or what?
Gentlemen, you can't fight in here, this is the War Room!
A galactic habitable zone is the zone within a galaxy where stars around which planets that could support life can form. A solar habitable zone is a zone within a stable solar system that plantets may form and sustain life. This extends the latter, but not the former.
https://www.gnu.org/philosophy/free-sw.html
> Under some circumstances water might even be found inside Uranus
I think that is called "diarrea"
Under some circumstances water might even be found inside Uranus...
Umm, not if I have anything to say about it!
Could someone explain why life is impossible on Venus. I know that it is 400C with suphuric acid/carbon dioxide atmosphere, which will stop any life from starting now.
But this would of gradulary developed, Venus started in similar condtion to Earth, therefore any life that managed to get a toe-hold on Venus would have had time to adapt their bio-chemistry in a similar way to those of the Earth's sub-sea vent creatures (~150C, high sulphuric acid concentrations).
I have heard that 'Oxygen destroys naked DNA'. Therefore there can be no DNA-based life on Sol 3, but when we look at Sol 3, we are hard-pushed to find somewhere where there isn't life of some sort.
It has become appallingly obvious that our technology has exceeded our humanity. --- Albert Einstein
There really aren't a lot of other choices. It is unimaginable really to have life (at least any kind of life we could interact with) in solid or gaseous form, so you need a solvent. Methane, carbon dioxide, helium, and hydrogen are abundant but nowhere near as versatile as water. Liquid ammonia or some mix of solvents might work, but they don't look promising.
So, people have thought about this but not really come up with any plausible alternatives so far. Water and carbon seems to be the only reasonable cohice. But if someone can make a plausible argument, I think the scientific community is receptive.
If you think about it... take a bunch of primordial star-material. condense it into a system and let the planets cool for a few billion years. At that point, you will find water. And you will most likely find liquid. But Earth is at the triple-point of water... we have it in solid, liquid, and gaseous form. I would think that would be more important to fostering life than the mere existance of water, or of liquid.
By his definition, yes. Of course, computer viruses are artificial (life?). But life was a pre-requisite for their creation (i.e., us).
In any event, if we observed a natural phenomenon that behaved like a computer virus in those respects, then it would probably qualify as a life form.
I found this interesting article on it even more indepth info.
Except instead of stating it "If there cannot be life, then there is no water", it makes more sense to say "It is not true that life is impossible where water exists." Or "Either there is no water, or life is possible."
No come on geezers... there is only ONE solar system... SOLar means "realting to SOL" which just happens to be the name of our star. Thus there is only ever one solar system... help pedants around the world stamp out this improper use of "Solar System" :o)