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Lake spotted on Titan?
jahead writes "It looks like
a lake has been seen on Saturn's moon Titan by the Cassini probe. But don't get too excited yet. As mentioned by Elizabeth Turtle in the article, it could also be a dried up lake that left dark deposits."
What do you moderators not understand about "I'm not trolling, I'm curious."? I'm looking for more knowledgeable people in the Slashdot community to answer the question of the finding's significance. It's one thing to find something, and report it, but TFA gives no reason as to why this is important. Does it allow for future bases on Titan to somehow suck up methane for fuel? Is there the possibilty of methane-based life that might live in a methane lake? I'd like to know why this is important.
libertarianswag.com
I am more interested in what Cassini finds once it gets to Europa. A possible methane lake seems inconsequential compared to the supposed "water world" of Europa. Then again, I suppose if it was in the neighborhood, it might as well check out Titan and see what's shakin, or lakin' as the case may be...
Well, besides beings merely interesting, it's nice to see what were previously thought to be Earth-unique features on other bodies. Lakes and rivers aren't really found anywhere else, maybe at one point Mars, and maybe longer ago on Venus. To find a lake and a full water cycle, even if it's really methane, is significant because that brings our counter of objects which have lakes and rain up to 2. The more often we see simliar features and objects on other bodies, the more we can expect to find a useful combination of those same features out there sometime in the distant future. For some, it's comforting to know that you're not a fluke.
Fnord.
I think the major thing of interest here is that Titan is so different to any body in our solar system (other than Earth, of course). The fact that liquid of any kind exists is quite remarkable. It means it has been able to retain pretty much all of it's initial components, unlike most other rocky bodies that heat up and lose a lot of their original constituents. Titan is, I believe, a kind of mini proto-planet. It's similar to how Earth would've been when it was young. The difference, however, is that Earth was in a position to heat up and eveolve, whereas Titan is perpetually frozen. There's a lot of fascinating science there.
As for methane-based life, I think it's unlikely just because of the extraordinarily low temperatures on there.
You would hope us humans would have learned out lesson about draining the natural resources by then.
Uhm, not to be obtuse, but why shouldn't we drain and use the oil here on Earth? Do you think that if we leave it in the ground, it'll somehow eventually turn back into dinosaurs? It's a plentiful, efficient, portable, cheap (relative to the alternatives) energy source.
The problem with oil isn't that we're using it - it's that we have no plan to handle the byproducts produced by using it. The pollution is the problem. Global warming, smog, and all that. There's no benefit to leaving the oil in the ground and switching to more expensive energy sources before it's necessary.
Like woodworking? Build your own picture frames.
From my limited astronomy background (wasn't my major, but it fascinated me so I paid attention): Through modeling, we can assume that what holds on Earth, should hold on other planets, other galaxies etc.
I think what we are forgeting is that it seems that we know less about space than sometimes we think. For example, if memory serves me right, there is a lot of dark matter in the fringes of the galaxy- we know it is there because something is having an effect on other bodies there, however we can't detect it because it doesn't seem to emit any known energy source... (Caveat- I am not an astronomer, just a hobbyist, so take my assertion with a salt grain)
So in my line of reasoning, it seems that this lake on Titan may not have the same characteristics as a similar lake on Earth, for a plethora of reasons that we may not understand yet.
All that aside, how cool would it be to swim on another planet, even if in a lake of methane...
And for those with tinfoil hats- keep in mind that some assume that we don't get real info from NASA- such as those who say that gravity on the moon is much closer to the Earth's gravity, unlike what we are told, but this can't be released because it would throw a Geurilla Wrench into the theory of relativity....
And All I Ask is a Tall Ship And a Star to Steer Her By
I guess I do not understand your meaning. If anything, a solid requires more pressure than a liquid. If you have a system (held isothermal) composed of a gas and you increase the pressure, what happens? It condenses to a liquid. Continue to increase the pressure, and then what? Your liquid freezes to a solid.
Given the context of space, I think I see your intention. That is, at extremely low temperatures a pressure change would most likely result in either sublimation or deposition. However, on a celestial body you can get greater temperatures than that of the vacuum of space.
-KD
but why shouldn't we drain and use the oil here on Earth?
See your answer below.
The pollution is the problem. Global warming, smog, and all that.
"It's not the shooting that's the problem... it's the holes poked in everything! Just because we don't have a solution now is no reason to stop shooting indiscriminately."
=tkk
Bill Gates - Creationist?!?
So we are sending all these probes.. Mars and Titan for example.
What if one of them returned images of cities, or villages, either deserted or actively inhabited. - What do you think would happen? Would there be a giant cover up? Or maybe a giant newsflash? Would those responsible for the probe just publically "forget" that they ever sent a probe there?
Don't Tread on Me
The reliance on fossil fuels does put limits on our energy expenditures. If we do succeed in producing fusion power cheaply we will have a new form of pollution; heat. Even if we move to non-polluting forms of energy production other than nuclear we will still be left with heat. In my opinion once you remove the spectre of visible pollution that we have with today's fossil plants many people will be hard convinced that there is any pollution left, after all its "green power".
While we all can agree mankind affects his global environment we cannot agree to what extent he does. Everyday something new comes up that throws a wrench into every argument made pro and con. Understanding more about how other planets work may lead to better insights here.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
Umm. . . No.
.something, and that's about it for the bodies in the solar system.
Io was the second known body to have liquids on its surface (1979 Voyager flybys discovered active, extrusive volcanism). Titan was next, though we couldn't see through the clouds, so we had no idea. Triton was the fourth to possibly have liquids on its surface, though we still don't know for sure. Venus also likely has some liquid lava on its surface, though we've not seen actual volcanism. Plus, Venus probably sometimes has sulfuric acid rains, but we're not sure. Mars may also have transient liquids on its surface.
Titan's cool because it's probably got an active hydrologic cycle (don't read hydro- to mean water, read it to mean fluid). Earth does, Venus might, Io has. . . something, Mars had one, it might still, occasionally. Triton has. .
Earth is a big body, so it still has radionuclide heat, and it's close to the sun, so it's got an abundance of energy to drive a hydrologic cycle. We can't see through Venus' clouds with more than RADAR, so we don't know what's going on there. Mars is small, so its heat has mostly left it, and it gets nearly 1/4 the energy the Earth gets from the sun, so it's cold and has little atmosphere left. Io is in a weird, slightly eccentric, orbital resonance, so its energy comes at the expense of Jupiter (and Ganymede and Europa). Titan's also in an eccentric orbit, but it doesn't have the resonance with other sats that Io has, so it "should" have lost most of its energy--one of the mysteries is why such a small body has such a huge atmosphere (and thus a hydrologic cycle). Triton might have a bit of an atmosphere, and why is also a mystery.
So, of the many, many bodies in the solar system, there are only a few that have atmospheres, and fewer that have an active, observable hydrologic cycle. . .
that's sort of a silly analogy, because shooting indiscriminately doesn't really result in anything productive. We aren't burning billions of gallons of oil per day just for fun. Fossil fuels have helped us create all sorts of neat technology and culture and things.
Who knows if we would've gotten this far without them. Is it realistically possible to go from water and wood burning straight to nuclear and solar? Could we have made the leaps in technology that we have without such a cheap and abundant energy source waiting for us right in the dirt?
Fossil fuels have been quite a step in our energy generation timeline. It has had plenty of unforeseen consequences, but that's life. Now, you can certainly argue that humanity, as a whole, is dragging its feet instead of moving along to the next step, but that doesn't mean that fossil fuels are evil or have been a waste of humanity's time.
Let me try and balance out your analogy with one of my own:
Walking is more efficient for humans than crawling, yet we don't scold babies for crawling on all fours instead of running around on two feet. We understand that it's one step in the process, and as a child grows, it makes better choices and becomes more efficient with its energy.
One time I threw a brick at a duck.