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Titan, one of Saturn's moons, has an underground ocean (nasa.gov)
178 points by rblion on July 30, 2012 | hide | past | web | favorite | 40 comments

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 further than all the excitement every six-wheeler is experiencing right now, as they watch their six-wheeled brothers, the daring explorers of Mars.

I am an engineer. I can comprehend and I do have the ultimate respect for the genius that allows us to land and operate robots on Mars, but that's the same genius that allowed us to land people on the Moon and, sadly, this is something we don't do anymore because it's too expensive. And we refuse to spend money on that while, at the same time, we fight unnecessary wars against the dictators we financed in the past. There is water ice on the Moon, probably a lot of it. There are minerals, abundant energy, just enough gravity to make industrial processes easy and a high grade vacuum that's the dream of every metallurgist. With these resources, we can become a true spacefaring civilization fit to meet our neighbors from the other islands floating around our sun.

We shouldn't do with robots the work of humans.

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 reasonable budget.

Cost is the main reason robots have gone all over the Solar System and beyond, and the farthest any humans go these days is to LEO to hang out at the ISS.

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 doing anything.

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.

It won't become cheaper and safer to get humans into space at any reasonable pace if we keep focusing all the R&D on how to get robots out there in a cost effective way.

Have you seen the type of landing solutions they're coming up with for the robots? They're all going in a direction driven by the realization that since they're not humans, they can afford to take far higher risks and subject them to stress that would otherwise be completely intolerable, so they're explicitly not trying to address the complexities of bringing humans into space.

I'm happy for work on robot probes to go on, but that's no reason to not also invest more resources in the groundwork for cheaper human space flight.

There's no reason to put humans out there. There are no aliens. There's nothing out there for us. That's why we send probes. Cheap probes. Unmanned probes.

If we happen to discover something amazing that would be interesting or beneficial to walk up next to at incredible risk and expense, then perhaps we would do a manned mission. But its far far too limiting to send people in every direction to do the exploratory probing. You can explore a 1000x more volume of space with robots than you can with manned missions. We can't even see anything worth sending humans to with telescopes.

We don't make manned space probes for roughly the same reason we don't make manned torpedos. There's no point to the expense and risk. Use the right tool for the right job and put down the science fiction.

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.

It doesn't disprove anything. We spent a few percent of GDP for a few years to get a dozen people on the moon then we got bored then cut the budget. I'd greatly expand NASA's budget, explore the solar system, build the tools to start constructing on Mars/Moon, etc and hoping find a great reason to send people.

"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."

It is entirely possible that our first contact with intelligent life will be with that life's robots. Just saying.

Robots are a cost-effective way to explore space. You can send them on missions that don't have to be hyper-controlled for the preservation of life. You can send them on one-way missions, vastly extending the distance that a mission can cover. With manned missions, by contrast, the loss of even one life is an unacceptable casualty. Ergo, you need to overengineer the craft, and also load it up with all manner of food, living space, life support, waste management facilities, sufficient fuel for a return voyage, etc. -- all of which add lots of mass to the craft, which adds enormous fuel costs, etc.

I agree that we should return to manned space exploration as soon as possible. That said, I don't find space exploration to be a zero-sum game between manned and unmanned missions. We should be using a diversified approach -- one that focuses on manned colonization, coupled with robotic deep-space exploration and surveying.

About the "too expensive" argument. That is one of the worst misconceptions the general public ever had. I'm a peace-loving person but every time I hear somebody complain about giving funds to scientists I want to punch them in the face. The UK spent more money on the banks in one year than they did on science since Jesus (at least that's what I heard on some BBC show lately - however it's all way out of proportion).

If we spent just a comparably tiny bit more on science, I believe the advances would be absolutely huge. Science drives technology, which in turn drives the economy. It's a win-win for everybody and yet we keep putting our money into things that have proven not to work reliably in the past without a second thought.

(On a sidenote: I do tend to get quite angry when speaking about banks these days, please excuse that ;))

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 lifting with robots. And if I were one of those colonists, I would sleep easier under the martian moons knowing that I had an army of space robots to help me with any problems that arise.

Humans find ways to explore the universe while keeping themselves alive. Let's embrace it

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.

Sure, but whose name do we remember? Whose story do we tell?

For better or worse, humans are narrative creatures. Note the recent talk of funding a Mars mission by treating it as a reality show.

Our approach is reasonable. But since people are unreasonable, the reasonable approach may not be the best one.

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.

You've got a point there. I'm not saying we shouldn't use robots extensively, just reacting to the idea that "humans don't belong in space, it's too expensive".

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

With all due respect this is like saying we shouldn't use rockets to go into space but instead try to jump higher. Humans using their big monkey brains to make technological advancements is the core of space exploration. We should be inspired by the people designing and operating the technology. Probably more so than the (mostly) non-scientists and non-engineers who flew rockets to the Moon for example.

I can't disagree more. What I'm interested in, and I think what scientists are interested in, is to explore, to understand, to discover. Robots are a manifestation of humans: it's a tool for us. A tool that is better than risking life of astronauts or spending a lot of money just to have that cow boy feeling of "I was there with my foots".

As much as I want to commiserate with you about sending humans into space - I have to remind myself that this is an escapist's fantasy. I am also an engineer, and a realist.

We just happen to be tied to a water-filled, fertile, and atmospherically suitable planet - the only one of this kind we can reach with our current technology. Looking to the stars is an easy way to ignore problems of over-consumption, over-population and climate change. If we don't figure out how to live on this planet, we are doomed to repeat the same mistakes elsewhere.

Let's pull our gaze back down to Earth: our capital is better spent addressing Earthly problems vice sending us out on an inter-planetary expedition.

I think there's a middle way: double-down on sending robots to space, which technologically and economically spurs innovation and sustainability on earth, that we might someday be in a position to send humans to space for extended stays.

Planetary Resources is going in the right direction. Capturing humanity's imagination is a good start; capturing their investment capital is what actually gets things done.

I'd second that. By no means would I want to see space exploration stop. I just don't think we should be looking to live elsewhere when we can't live here.

I couldn't agree more, however, if humans are too expensive, I still don't mind the robots getting there first. The moon landing was an outcome of the cold war. I find it hard happening again. Sending humans all the way to Saturn - it is very far away - is a dangerous task with too much at stake.

I would love for all wars to end, for all the military budget to go to NASA instead, and for us to become a truly inter-planetary civilization, but that's just not a realistic wish, at least not for the next decades.

But robots. Robots we can do now. Curiosity landing on Mars next week. It can do truly amazing things, scientifically more than a team of humans could.

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

In case anyone's counting, this makes it the 5th planetary body in the solar system with a high likelihood of having an ocean (Earth, Europa, Ganymede, Callisto, and now Titan).

Add to that a parcel of additional moons and other other bodies that show indications of having sub-surface oceans (Triton, Enceladus, Pluto, Rhea, Titania, Eris, Sedna, Orcus, and Oberon).

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?

Perhaps by "molten ice" he means that the H20 is in its liquid state not because of the surrounding temperature but because of the pressure exerted upon it by the upper layers. Just a guess.

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).

I see no special "molten ice":


It might have an exotic form of ice, of course.

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.

Oh, definitely. I was (poorly?) highlighting that molten/frozen/vaporized/etc are used relative to the normal state for a substance at "local" temperature.

Link to abstract of the original research paper in the journal Science: http://www.sciencemag.org/content/337/6093/457.abstract

...and for accompanying news article in Science: http://www.sciencemag.org/content/336/6089/1629

... and here is how we get there, similar to how Bill Stone proposes we get to Jupiter's moon Europa: http://www.youtube.com/watch?v=-Bn6Gel7yEs#t=6m9s

Thanks for the link. And just in case you didn't know, you can add #t=6m9s to youtube links to make videos start from that point: http://www.youtube.com/watch?v=-Bn6Gel7yEs&feature=playe...

Reading this article gave me a glimpse into the richness of extra-terrestrial biosphere processes. Even if Fermi's right and we never find life, there's a lot of stuff left to observe, study, and learn about, like the methane cycle on Titan.

I do wonder, if NASA said they found oil on another planet or moon what the reaction would be. After all it would be a sign of past life on that planet, though I feel that alot would see it as a opertunity to claim more oil.

I just hope the first aliens we encounter are not plant based or they will take one look at us and our use of there dead relatives and it will not go well. Food for thought.

Unless it was economic to extract the oil and return it to earth (which it would not be) the discovery would be mostly of a scientific nature. However, finding hydrocarbons on the moon would be a good thing insofar it would provide a ready energy source for any future moon-based operations.

The reason oil is so popular is because it is so useful. Anything useful is in high demand. There's no need to get hysterical about it.

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