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Titan, one of Saturn's moons, has an underground ocean

science.nasa.gov

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Re: Titan, one of Saturn's moons, has an underground ocean

#21

Post by riledhel »

hooande wrote: post #18
rbanffy wrote: post #8

Please, can we now put a reasonable nuclear reactor in space, power a VASIMIR engine (or something equally adequate), and do it with humans instead of robots? We already proved we can do it with machines and who will make first contact with alien life in becoming a really important question. We are not a race of robots. People wonder why the general public lost interest with space exploration, but we need to look no…

Do you think that the great explorers of the past would have risked their lives if they could have avoided it? Danger is a big part of the adventure of exploration, but no one wants to die unless it's absolutely necessary. If Colombus could have sent a robot, he would have. The bottom line is that Bags of Mostly Water don't belong in space. Our only hope for colonizing the solar system is to do most of the heavy lift…

In the same spirit of your comment, Colombus didn't send other people to do his job/wish/quest, he wanted to go west.

Re: Titan, one of Saturn's moons, has an underground ocean

#22

Post by awj »

recampbell wrote: post #9
quotemstr wrote: post #6

It's not really an "ocean" in the way we think of such things. In the outer solar system, ice is a rock in the same way granite is a rock. What Titan has isn't so much an ocean as an interior layer of molten ice --- just as our planet has an interior layer of molten rock.

Can you expand? Why does the article call it "liquid water?"

It's "liquid water" in the same sense that the molton rock inside the earth is "liquid rock".

Here when we see water outside of it's natural state (liquid) it's frozen or evaporated. Out there ice (solid) is the natural state, so it's molten or (vaporized ???).

Re: Titan, one of Saturn's moons, has an underground ocean

#23

Post by icegreentea »

bcbrown wrote: post #7
quotemstr wrote: post #6

It's not really an "ocean" in the way we think of such things. In the outer solar system, ice is a rock in the same way granite is a rock. What Titan has isn't so much an ocean as an interior layer of molten ice --- just as our planet has an interior layer of molten rock.

What's the difference between "molten ice" and water? Is it still crystalline? Is it just the pressure is different, or is there actual physical differences?

I don't think it's so much a physics/chemical difference, but more to the effect that here on Earth, the ocean is a large body of water that sits on top of the stuff the Earth is actually made of (which is a solidified crust on top of the semi-liquid rock of the mantle)

On Titan, the role of the semi-liquid rock is played by the "ocean" (and the crust is played by the solid water ice layer ontop).

Re: Titan, one of Saturn's moons, has an underground ocean

#24

Post by rblion »

rbanffy wrote: post #8

Please, can we now put a reasonable nuclear reactor in space, power a VASIMIR engine (or something equally adequate), and do it with humans instead of robots? We already proved we can do it with machines and who will make first contact with alien life in becoming a really important question. We are not a race of robots. People wonder why the general public lost interest with space exploration, but we need to look no…

The trillions we spend on war and rebuilding the wreckage could be applied to reach new worlds and truly become Homo univeralis.

Re: Titan, one of Saturn's moons, has an underground ocean

#25

Post by yajoe »

andrewflnr wrote: post #19
hooande wrote: post #18

Earlier quoted context omitted.

Do you think that the great explorers of the past would have risked their lives if they could have avoided it? Danger is a big part of the adventure of exploration, but no one wants to die unless it's absolutely necessary. If Colombus could have sent a robot, he would have. The bottom line is that Bags of Mostly Water don't belong in space. Our only hope for colonizing the solar system is to do most of the heavy lift…

I don't believe Columbus would have sent a robot. Sure, explorers would rather not die exploring, but generally, I don't think that not being there is an acceptable price. Would you send a robot to the top of a mountain if you could, or do you want to climb it yourself?

A subtle point is that the Spanish royalty funded and helped organize Columbus, but none of the royalty accompanied Columbus. Why? Back then class and "castes" had significant meaning. The decision-makers sent expendable people similar in spirit to the way we would send expendable robots.

Our approach today is not unreasonable or atypical of past expeditions.

Re: Titan, one of Saturn's moons, has an underground ocean

#26

Post by melling »

andrewflnr wrote: post #20
mikepurvis wrote: post #10

Earlier quoted context omitted.

A lot of the Rocket to Nowhere arguments address your points: http://idlewords.com/2005/08/a_rocket_to_nowhere.htm In short, as soon as large hairless mammals are involved in the mission, 99% of the mission's resources are suddenly consumed with keeping said large hairless mammals fed, watered, breathing, amused, etc. So basically, there's nothing left to do anything of much value, especially on any kind of reasonabl…

Yeah, but the whole point of the mission, robots or no, is to benefit large hairless mammals. So if the hairless mammals think it's to their benefit to be on the ship, that's where the resources go, assuming they can get the resources together. Of course if that's not the goal of a given mission, then robots are more likely. Yes, humans make everything more complicated, but without them, there's not much point in doi…

I'd say this is completely wrong and this attitude is preventing us from advancing more rapidly in space.

There's a lot to yet to discover in space. Developing better tools, robots for example, to explore our solar system will also benefit us on earth. At some point the costs will drop and it will become safer, or we'll discover something valuable that we'll want to bring back.

If you look 100 years out, which route get use to having he most people in space? Let's release early and release often.

Re: Titan, one of Saturn's moons, has an underground ocean

#27

Post by melling »

andrewflnr wrote: post #19
hooande wrote: post #18

Earlier quoted context omitted.

Do you think that the great explorers of the past would have risked their lives if they could have avoided it? Danger is a big part of the adventure of exploration, but no one wants to die unless it's absolutely necessary. If Colombus could have sent a robot, he would have. The bottom line is that Bags of Mostly Water don't belong in space. Our only hope for colonizing the solar system is to do most of the heavy lift…

I don't believe Columbus would have sent a robot. Sure, explorers would rather not die exploring, but generally, I don't think that not being there is an acceptable price. Would you send a robot to the top of a mountain if you could, or do you want to climb it yourself?

No, the guy 100 years before him would have. Meaning the first guy who had the robot. They would have measured how long it took, known the best routes, then tens of thousands of people would have followed shortly thereafter because a lot of the danger would have been taken out of the voyage.

Re: Titan, one of Saturn's moons, has an underground ocean

#28

Post by Synthetase »

melling wrote: post #26
andrewflnr wrote: post #20

Earlier quoted context omitted.

Yeah, but the whole point of the mission, robots or no, is to benefit large hairless mammals. So if the hairless mammals think it's to their benefit to be on the ship, that's where the resources go, assuming they can get the resources together. Of course if that's not the goal of a given mission, then robots are more likely. Yes, humans make everything more complicated, but without them, there's not much point in doi…

I'd say this is completely wrong and this attitude is preventing us from advancing more rapidly in space. There's a lot to yet to discover in space. Developing better tools, robots for example, to explore our solar system will also benefit us on earth. At some point the costs will drop and it will become safer, or we'll discover something valuable that we'll want to bring back. If you look 100 years out, which route…

We've taken the probe launching approach for the last fifty years. Besides SpaceX, launch tech hasn't really advanced since then which really disproves your thesis.

We must stop our collective procrastination. Human spaceflight is the ultimate forcing function.

Re: Titan, one of Saturn's moons, has an underground ocean

#29

Post by aprendo »

Synthetase wrote: post #28
melling wrote: post #26

Earlier quoted context omitted.

I'd say this is completely wrong and this attitude is preventing us from advancing more rapidly in space. There's a lot to yet to discover in space. Developing better tools, robots for example, to explore our solar system will also benefit us on earth. At some point the costs will drop and it will become safer, or we'll discover something valuable that we'll want to bring back. If you look 100 years out, which route…

We've taken the probe launching approach for the last fifty years. Besides SpaceX, launch tech hasn't really advanced since then which really disproves your thesis. We must stop our collective procrastination. Human spaceflight is the ultimate forcing function.

Because we haven’t put any resources into it. Everything was sucked up by that goddamn stupid human spaceflight.

There could have been so many Cassinis, so many Spirits, so many Opportunities. But, no. Stupid humans in space.

Re: Titan, one of Saturn's moons, has an underground ocean

#30

Post by sliverstorm »

awj wrote: post #22
recampbell wrote: post #9

Earlier quoted context omitted.

Can you expand? Why does the article call it "liquid water?"

It's "liquid water" in the same sense that the molton rock inside the earth is "liquid rock". Here when we see water outside of it's natural state (liquid) it's frozen or evaporated. Out there ice (solid) is the natural state, so it's molten or (vaporized ???).

If it's subterranean, it's probably not vaporized. Thank the pressure.
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