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entered_bubble_50 OP t1_j6u6sy1 wrote

We can possibly add this to the list of moons that appear to have sub surface liquid oceans. So far, it seems there are liquid water oceans on present on Titan, Europa, Enceladus and possibly, Callisto, Ganymede, Triton and now Mimas. Crazy!

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Bewaretheicespiders t1_j6uc639 wrote

Radiation as high as 0.1 rad /sec on Mimas... we're not about to go dig there.

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beaucephus t1_j6ucgtm wrote

Replying to Blazin_Rathalos (#1,698,527)

On Titan the "rocks" and mountains are made of mostly water ice. It could mean that Titan has water "magma" at depth with dissolved hydrocarbons. There are lots of possibilities, but of course, all speculation.

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gregarioussparrow t1_j6uiaug wrote

I do find it arrogant that we assume all life needs oxygen and water like on earth.

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FireTyme t1_j6uou38 wrote

Replying to gregarioussparrow (#1,698,864)

complex life most likely does. it’s not that arrogant really when u think about it. life needs to be able to create and preserve energy. it’s much harder to create energy when ur environment is incredibly cold. and much harder to preserve energy due to that reason as well.

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1992PlymouthAcclaim t1_j6upw4i wrote

Replying to FireTyme (#1,699,232)

Agreed. PBS SpaceTime posted a really excellent episode the other day outlining the challenges that silicon-based life would face in (most) natural environments. I, like OP, had long assumed that our preference for "life as we know it" was a bit of a blind spot -- I no longer think so. There are so many obstacles standing in the way of the organic evolution of silicon-based life that it wouldn't make sense (in most environments) for nature to favor silicon over carbon.

Given a) the goldilocks scenario that gave rise to life on Earth and b) the apparent dearth of life elsewhere, I think it is reasonable to suspect that it is very difficult for complex life to spring up just about anywhere. Silicon-based life would face an even steeper degree of difficulty. Environments without water (an ideal solvent for the mixture of molecules) might just render the appearance of complex life next to impossible. We can't know that for certain, of course, but I think it's completely reasonable to narrow our search (for the time being) to environments that seem conducive to life rather than expending energy and resources on locales where we have no reason to think that life is even possible.

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gulgin t1_j6uq3o3 wrote

Replying to gregarioussparrow (#1,698,864)

Oxygen and water (and to a lesser extent carbon) are very unique in the universe in terms of the convenience of reactions and processes that are easily cyclical. Water has some great properties that help with fundamental chemical processes that aren’t found often elsewhere.

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VoraciousTrees t1_j6uq6u8 wrote

Replying to Bewaretheicespiders (#1,698,552)

Earth background is .3uSv/hr = .00003rad/hr.... rads halved by 7cm of h2o shielding... Surface rads at 360 rads/hr... 360*(.5)^x = 3E-5 -> 3E-5/360=.5^x

Log(12E6^-1) / Log(.5) = x

x = ~23.5

23.5 * .07m = ~ 1.65 meters of ice.

So TLDM : If you stay under about 1.7 meters of ice (maybe a little more due to density concerns) you should only experience normal earth background radiation... on paper.

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somethingicanspell t1_j6uyvtc wrote

Replying to gregarioussparrow (#1,698,864)

I’ve never seen a convincing alternative to carbon for chemical based life. Yeah you could use Sulfur, Boron, or silicon but they all are much worse and couldn’t form anywhere near the same amount of stable compounds or in borons case is just much rarer

Water and Oxygen both have alternatives but are probably the most likely compounds used by life because they are ubiquitous, usable at high temperatures, and/or have simpler mechanisms than their alternatives. I’d put complex chemical life at about 99% for carbon, 80% for water, 50% for oxygen.

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JuuzoLenz t1_j6v2ltb wrote

Never though that stealth ocean world would be something I would read one day

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TheGreatestOutdoorz t1_j6v37fs wrote

Replying to 1992PlymouthAcclaim (#1,699,317)

When I went to college, I thought it was so ridiculous that we assumed life had to be carbon based. I majored in biochem and quickly learned why carbon is almost certainly the only base for complex life, and while it kind of made me sad, it was incredibly cool to think about different ways carbon could create complex life forms.

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idontknow7272 t1_j6vhbyz wrote

That's no moon!

Sorry. I couldn't resist. It's actually one of my favorite moons.

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Benjilator t1_j6vt34y wrote

Replying to AWizard13 (#1,701,422)

I’m a chemist and I don’t think there’s anything you can’t get out of your water so it should be useable in any case. Every other way of getting water will be cheaper, though.

But basically you can just make pure water out of it and add the minerals in later, pretty sure that’s how a lot of our water is made already for consistency.

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isleepinahammock t1_j6vuulr wrote

Replying to Blazin_Rathalos (#1,698,527)

Titan's surface seas actually interest me a lot more than the water oceans of the ice shell moons. This is for a couple of reasons. First, they're a lot more accessible. You don't need a probe capable enough to land, drill/melt through miles of ice, etc. You can plop down directly in them from space and start exploring. They're exposed directly to the atmosphere.

But that's not the real reason I'm interested in Titan's hydrocarbon seas. People have come up with speculative models for life that could actually exist in this environment. I'm not talking about microbes hiding out in the liquid water mantle of Titan, I'm talking exotic life that actually uses methane or ethane as its solvent, as Earth life uses water. Biologists have proposed models for such life forms and how their biochemistry could work.

Why is this so interesting? For one, it would just be a really neat discovery; it would prove that our type of life isn't the only type of life possible. But it goes much deeper than that.

Let's say we find some microbes in the waters of Europa or hiding in a briny aquifer in Mars. That would be a neat discovery, but we'll quickly run into a problem; how do we know that this life truly represents a second case of abiogenesis? In other words, how do we know that the microbes or other life we find is actually a truly unique instance of life? If panspermia is in play, then it's entirely possible that life originated on Earth and then was transferred to the other bodies in the Solar System. Or, life could have originated somewhere else and been transferred here. We have examples of Martian meteorites on Earth; we know that the various planets have all contaminated each other with some of their surface rocks. It's hotly debated whether microbes or their more durable spores could survive being launched into space by an asteroid, drifting for years in the vacuum, and then survive crashing onto another planet or moon. But the important part is that is a possibility. It's by no means proven, but it's not an unreasonable hypothesis.

If we find these microbes on Mars, biologists will immediately try to sequence their genomes and see if there is a common ancestor with Earth life. But the big problem is that ambiguity will still exist. We can't for sure know what kind of microbes existed on the early Earth. Even if the life we find seems to be evolutionarily distinct from Earth life, there will always be a possibility that the microbes we find are simply descended from a now-extinct branch of Earth life. Especially if it largely uses the same chemical elements as Earth life, whether such life is truly a second genesis will remain ambiguous. Biologists will debate the topic for generations, arguing for this reason or that reason why Earth life and Mars life do or do not have a common ancestor. We may never get a firm answer.

And this answer matters because what I'm ultimately most curious about is how common life is in the universe. If life on Mars and Earth share a common ancestor, we just go from only knowing that one planet has life to only knowing that one solar system has life. We could just be from one freakishly lucky solar system that happened to have an abiogenesis event, and almost every star in the sky is orbited by completely dead worlds. However, if we had clear evidence that two genesis events happened in one solar system, it would mean life is everywhere. Life cannot be incredibly rare if there are two independent occurrences of it in just our star system.

And that's where the potential of Titan's seas really shines. It may be possible for life to exist in Titan's seas, but it would have to be, from the molecular level up, constructed completely differently from every life form on Earth. I've heard it eloquently describe that, "such life would be as different from us as a stone fish is from a stone." There is zero chance that a microbe that uses methane or ethane as a solvent and can only exist at temperatures cold enough for liquid methane will share any ancestry with Earth life. The discovery of a single microbe in Titan's seas would represent an undeniable, completely unambiguous example of a second abiogenesis event. In an instant, we would know that life is absolutely everywhere in the universe.

I see life in Titan's seas as the hail Mary play of astrobiology. Though we have some conjectural models for how such life might work, we have no way of knowing if such life is truly even possible. No one has managed to assemble such a microbe in a lab. So it's a huge gamble whether such life exists. But if it does, it would provide unambiguous proof that life is everywhere in the universe. It's the ultimate high risk/high reward gamble.

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ruetoesoftodney t1_j6wclg5 wrote

Replying to alvinofdiaspar (#1,698,572)

Just fyi with liquids it's commonly called an azeotrope, not a eutectic (which is for solids despite them being the same thing in two different phases).

Primarily different terms because it's different branches of engineering that deal with the two.

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John_B_Clarke t1_j6wtuic wrote

Replying to Benjilator (#1,702,322)

Every drop of water on a space station has been carried there by humans in some form or other. And every gram of hydrogen and oxygen that are expended as rocket fuel in interplanetary space is pretty much nonrecoverable.

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John_B_Clarke t1_j6wu8jk wrote

Replying to isleepinahammock (#1,701,613)

Many people make the assumption that DNA is the only possible carrier for a genetic code. If whatever life we find on Mars or Titan or elsewhere has a different molecule as the basis for its genetic code that would be pretty strong evidence that it didn't originate on Earth.

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therealdjred t1_j6wuqn3 wrote

This is such a shitty AI written article. Its got so many wrong words.

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SgtThund3r t1_j6xbvyb wrote

It was a diversion all along! Meant to ward off predators

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TheMurku t1_j6xqcld wrote

Replying to StygaiAsshai (#1,704,975)

'supplies' made me think you were referring to Life Support.

Apologies.

Seeing 'getting to orbit is halfway to anywhere' in Solar System terms what you suggest is absolutely the goal. It's called 'in-situ resource utilization', or ISRU. Water as a Reaction Mass (either as itself in NTRS or as a source of hydrogen) is the core material ISRU will seek.

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John_B_Clarke t1_j6xqvgy wrote

Replying to bucolucas (#1,703,578)

All the hydrogen and oxygen in those fuel cells was carried into space on top of a Saturn V. And it all burned up when the Service Module reentered. It is no longer available in space. And in any case, Apollo did not go to interplanetary space.

Read up about orbital mechanics.

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danielravennest t1_j6xy7x2 wrote

Replying to StygaiAsshai (#1,701,642)

There's plenty of water already in space. Some nearby asteroid types contain up to 20% water and carbon compounds. The carbon compounds typically have hydrogen, and that can be combined with mineral oxides (most rocks) to make more water.

Beyond the "frost line" in the middle of the asteroid belt, water can survive in a low-g vacuum environment, so there is lots and lots of water as water and ice.

Besides, most rocket launches produce more water than they can carry as payload. They take oxygen from the air and burn it with hydrocarbons. The exhaust is CO2 and water.

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iqisoverrated t1_j6y3mfz wrote

Replying to Rhombico (#1,705,055)

The radiation is coming from above (i.e from the direction of Saturn...and also from the rest of space...not from material on Mimas). Put a meter or two of ice betwen you and that and you're good.

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uglyspacepig t1_j6y5df9 wrote

Replying to entered_bubble_50 (#1,698,284)

I'm not sure Callisto belongs on that list. It's largely undifferentiated and not likely to have large pockets of water, let alone an entire ocean. But it's been a while since I've read anything new about it that assessment could have changed.

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Science-Compliance t1_j6y8lh5 wrote

Replying to IfIRepliedYouAreDumb (#1,705,727)

Because anything you do in space needs to account for the fact that you're floating in a void with essentially nothing around you but radiation. The materials have to come from somewhere, and you need to consider orbital mechanics to get from one body to another in space.

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Science-Compliance t1_j6y9u19 wrote

Replying to danielravennest (#1,705,493)

The exhaust from a rocket is basically unusable as a source of water for astronauts. Every drop of water you take from the exhaust, too, would be reducing the rocket's efficiency. In order for that rocket to work, you need all those combustion products to fly out the back of the nozzle at high speed. Anything you put in the exhaust stream that is attached to the ship is going to reduce the effective thrust of the rocket (assuming it doesn't just melt first). You'd be better off just already having a water storage tank on the spacecraft, but then we get back to the original problem.

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danielravennest t1_j6yc2bv wrote

Replying to Science-Compliance (#1,706,215)

I was responding to the "taking water from Earth" part of the previous comment. The exhaust from a rocket launch to orbit stays in the atmosphere.

(I've done space systems engineering for 45 years now, so I do understand how rockets work).

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Science-Compliance t1_j6z3txc wrote

Replying to IfIRepliedYouAreDumb (#1,707,893)

You don't have the privileged position to be making such condescending comments, and you still don't seem to understand the context of my and another person's comments. You should work on your own reading comprehension because you still don't seem to get it.

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amitym t1_j709r1s wrote

Replying to VoraciousTrees (#1,699,339)

Interestingly, the hypothetical ocean would be deeper under the ice than that, implying a much lower background radiation exposure than on Earth.

Which suggests a lower mutation rate for any life forms that live there. Although of course that might depend on whether they evolved to be more mutation prone as a meta-evolutionary strategy....

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DidItSave t1_j71skm2 wrote

Replying to RogerSmith123456 (#1,699,033)

For one of the research papers I was doing for my class, I came across a journal article that suggested if Ganymede gets affected by planetary migration, with tidal heating from Jupiter and radiation from the Sun, the subsurface water on Ganymede would make its way to the surface through geysers and cryovolcanoes. Combined with the magnetosphere, an atmosphere could form, eventually starting a hydrological cycle similar to that on Earth and Titan.

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StrangeTangerine1525 t1_j73tj9b wrote

Replying to isleepinahammock (#1,701,613)

Life on Europa and/or Enceladus was likely a second abiogenesis, the distances are just too vast for life to be seeded, even Mars there is something like a 1/10,000 chance if I remember, all three are just too far away, and either way, there is a pretty decent chance would be able to tell if the life we found came from Earth, with chirality and stuff like that.

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AWizard13 t1_j75fuxx wrote

Replying to TheAuthentic (#1,705,628)

I know! I do know that it takes a lot of energy and money to do, though.

I was wondering if like this water is composed differently and had a bunch of different stuff in it, would we be able to use it.

Or if it's not h2o and something completely different.

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