Might have been posted before...
ThomasGideon
USA Join Date: 2016-07-06 Member: 219745Members
USA Join Date: 2016-07-06 Member: 219745Members
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nah, neat video indeed
However, this 5% issue always annoys me a little. We've only explored 5% of the ocean? Well how are you defining "explored"? Because we've mapped out the ENTIRE sea bed to a resolution of 5km, so really, it's a little misleading to tell people we've only explored 5% because they will assume that means we have no idea what the other 95% is. The truth is, we know exactly what's going on, to within a certain point. It's not completely unknown, it's just that there doesn't seem to be anything there worth visiting based on what we can see from our current sonar mapping. We've mapped only 0.05% to within the highest resolution, but the endeavour continues. Eventually we will map it all to within metres, not kilometres.
(When people say "Why aren't we spending money on exploring the ocean first, instead of space?" the answer is, well, we are. And if we find anything worth going for a closer look, we'll be there right away. But so far we haven't spotted Atlantis on our sonar.)
And if exploration means "how much of the ocean have people seen for themselves" then 5% doesn't even come close, it's probably much, much less than that.
Anyway, good video. It's always fascinating.
Caps for effect
Actually, we know a lot from both soooo....
@ShuttleBug But we still know MORE
The leviathans could exist in our oceans......... [dramatic music]
At 50k, the pressure difference between max air pressure, or even compact metal (78k feet), would still result in the implosion of an probe sent that deep, preventing any studies of that deep, while geological evidence sugest that there are wide open caverns after trenches, which go to at LEAST 200k feet. so uhm, the moon, 99% has been mapped out (just the surface).
but, if u look at it from a amount of square feet of moons surface known to cube feet of ocean mapped out, we do know more, so my fault, but percentage wise, the moon rules supreme
@EnglishInfidel the reason they say 5%, is because the majority of scientists agrre that the 200k estimate above is correct.
some even believe it goes deeper. but at 400k feet to 500k feet, the temperature all around is hot enough to turn water into gas even with the pressure.
i would use the metric system but the video used feet
sorry for the caps neglect
How can you say that? We've sent plenty of ships, subs, probes, etc into the oceans. Granted, there is still much yet to explore. But the moon... we've never even been there. For all we know, it's made of cheese....
There is a maximum depth that something can live, if something large as a car could withstand the pressures that could crush a small submarine then that creature must have both the strongest and most dense bones, skin, muscle and organ tissue known to man. That tissue would be tougher then steel.
I giant jellyfish could survive down there since they are composed of 95% water and water is one of the most sence natural substances on the planet, so less reaper levithan more jelly or ghost ray.
That or flubber
Um, yes we have. Multiple times. Like, six of the Apollo missions have landed on the moon.
u never know....
THE FLUBBER LEVIATHAN
all liquids are like water. they cannot be compressed, but still impose pressure, technically making them stronger than any solid. it is always the container that breaks.
In short, lifeform absorbs water vapour, alters the pressure, to use, but the heat energy is still in the water, disallowing it to go into liquid state, allowing implosion or preventing respiration.
Then the Flubber Leviathan had to go and ruin everything.
Darn Flubber...
Many words of learning follow. Ye hast been warned.
Nope.
Leviathans are loud. We would've picked them up on SOSUS by now. Water's a beautiful conductor of sound energy; you can detect whalesong hundreds of miles distant from the actual whale. So a Reaper call would've been picked up on hydrophone arrays a long time ago. So, no to the leviathans.
The deepest spot in the Earth's ocean is the Challenger Deep, in the neighborhood of 35,000 feet. (Eh, let's call it 36,000 to account for uncertainty.) I'm not sure where that 50,000 number came from - let alone the 78,000 one - but it's not our ocean. And we've sent both probes and people to the bottom of the Challenger Deep. (Which the video pointed out.) No, there's no spot in our oceans that out of our reach; we just have very little reason to actually go.
The vast majority of the ocean floor is mud. If you've seen one square mile of it, well, you've effectively seen 'em all. Sure, there are some interesting features in the abyssal plains - black smokers, rock formations, whale falls, and the like - but otherwise: mud. That's not to say there aren't some nifty things down there other than mud, but you don't find those in the plains; they're big enough that we sonar mapped them ages ago. Mid-ocean ridges, trenches, continental shelves, seamounts - all very interesting (for a given value of "interesting") but there's really very little compelling reason to actually scope out endless miles of abyssal plain either in person or by ROV.
Well, now you're gaming the system. Since the moon's atmosphere is so tenuous as to be effectively non-existent, there is no "depth" axis to account for. Once we've mapped the surface, that's it, and that's square units. When you factor in the water column, you've changed the game and now you're talking about cubic units. You're comparing apples and cinderblocks. The whole "we've only explored 5%/10% of our oceans" schtick is a misnomer, but a useful one for illustrative purposes. What they're really saying is that there's enough uncertainty in those cubic miles of water that there can be lots of species we just haven't bumped into yet, and that's an accurate statement. But nailing a percentage to it is a pointless gesture if you're trying for accuracy.
These people hallucinate. Badly.
The ocean doesn't go deeper than 36,000 feet. Take it to the bank. There are no vast, subfloor submerged caverns, no lost worlds...none of that Jules Verne babble. And before the "well, we haven't checked everywhere!" argument comes up, here's its counter: we don't have to. We have done more than enough seismic and acoustic studies that we would've found some indication of such a system. To nobody's great surprise, we haven't. That doesn't mean that such structures can't exist anywhere, just that they don't exist here on Earth. Other planets can have somewhat different features.
@Jacke wins the cigar.
It's a common misconception that surviving in pressure requires strength. Armor. We get that idea because that's what we need to survive pressure. But the fact is that there are other structures in the World o' Biology other than human, and some of them do just fine in extreme pressure.
Interestingly enough, the few organisms that have been observed at the bottom of the Challenger Deep are largely soft-bodied: sea cucumbers and thin-skin shrimp. And, most critically, none have voids of any kind - not air, not oil. Those voids are what collapse from pressure, and why human lungs would collapse at sufficient depth. (Of course, a human would be long dead before reaching the body's crush depth from other causes, but that's a whole other conversation.)
Contrary to what every movie would have us believe, things don't just go splat under high pressure. The key element is that the body can't be compressible. Organisms like sea cucumbers do just fine even in the 16,000 PSI environment of the Challenger Deep because their bodies are mostly water; their tissues, which are pretty sparse by our standards, react to pressure with near indifference, so that's no problem.
(An intuitive idea of what 16,000 PSI is like: two loaded Ford F350 pickups sitting on each and every square inch. It'll kill you, but the sea cucumber likes it.)
Sorry, but no. And, while we're on the subject, water isn't completely incompressible either...but for all practical purposes, it might as well be.
It takes a lot of pressure to produce any noticeable compression in water. To gain an 11% decrease in volume, the pressure on the water has to be in excess of 58,000 PSI - and that's a lot more than the ocean has even at its best. There are some liquids that are even less inclined to compress: mercury is highly resistant (with a beta value of 3.7e-11 versus water's 4.6e-10), and glycerine (2.1e-10). But the vast, vast majority of liquids are compressible; it's all down to a matter of degree. Ethyl alcohol loses ten times the volume as water under the same degree of pressure, for example.
So, while we say water is incompressible, it isn't, not really. But for all intents and purposes, it may as well be; under the pressures that are part of our world outside of very small and dangerous lab experiments, the degree to which water compresses relative to other liquids is inconsequential. It's one of the many things that makes it just so darn useful.
If we're going to talk about water density then could I please mention the literal land of fire and ice
https://astronaut.com/the-planet-of-burning-ice/
https://en.wikipedia.org/wiki/Compressibility
This. So much this.
You will always be able to say "We just don't know what's there" but at some point you have to go with the most probable explanation; that there's nothing worth seeing. We have to look at what we do know and extrapolate from there, making very probable estimates about the 95%.
Same with the life down there in the deeps, sure, there are lots of things we haven't found. But are they worth finding? Probably not. Just a lot of micro-organisms and the occasional weird looking fishbeast or jellysack. But this 5% thing makes the average person dream of krakens and monsters, fascinating aliens right here on our own planet because there's 95% we don't "know" anything about.
There are no monsters, guys, just a lot of black darkness and the occasional mutant freak that's probably best left down there to rot.
(Side note, @scifiwriterguy obviously has a lot more patience than me. Respect.)
I Like It !!
You sure there's no Megalodon down there???
< snicker >
Finally, someone who thinks the same way I do.
Maybe there's one or two giant species still undiscovered down there, but the bulk of that 95% would probably be made up of micro-organisms, fish smaller than your thumbnail and more unimpressive creatures. If there were as many enormous creatures down there as people think there are, we would have found them by now, or at least found remains. If you want to find real life leviathans, Europa's the next place to look. The ocean's finished; we've seen all the good bits.
@Jamezorg i agree Europa has life. it would be more shocking if there was no life on Europa than life.
We know it has an thick icy surface, and evidence suggests it has water underneath. It would be like 4546B but colder and an icy surface.
Large-bodied creatures could exist with a simple-food chain.
#sendaprobetoEuropa
Srry to pick on u
Bacteria, Archaea, and similar life was all that was on Earth for most of its history. About 2 billion years ago, a number of rare events lead to a combining of them into Eukaryotes, the complex-structured cells that then evolved into all complex life forms. This is much less likely than the development of simple cell life like Bacteria.
https://en.wikipedia.org/wiki/Eukaryote#Origin_of_eukaryotes
I don't think I was clear enough; I don't believe there are actually leviathans on Europa, just that if you want to see real life reapers that's the only real place to look, because our own oceans definitely don't have them.
My fault, sorry.
Don't sweat it, dude.
Not necessarily, Jacke. Water and its ice are fantastic radiation shields. When you have a kilometer or so of solid-sheet ice, not much is going to get through, even from the radiation machine that is Jupiter. But even laying that aside, radiation isn't really a barrier to life. Complicating factor, sure, but life is...funny that way.
Radiotolerant organisms exist even on this planet. Deinococcus radiodurans was found growing near the blown-out core of Unit 4 in, yep, Chernobyl, and is even more durable. Thermococcus gammatolerans is the record-holder, able to tolerate doses even higher, finally crapping out around 30,000 Gy. But, granted, these are single-cell. Okay, how about tardigrades? Tardigrades can handle doses up to 5,000 Gy, about a thousand times what it would take to kill a human, and they're complex, multicellular organisms (albeit really tiny ones). The thing about life on Earth is that hard (ionizing) rads aren't really part of the picture for most of the planet.
Flip over to a radiosaturated environment. Any life evolving in that environment is going to be radiotolerant or even radiophilic; with hard rads bombarding the environment, selection pressure is going to favor first organisms that can tolerate radiation, and then those that thrive with it. Different environment means different rules, different pressures on evolution, and thus different outcomes. Could we find larger, more complex organisms in Europa's likely oceans? Sure. We even see examples of how they might tolerate such environments here on Earth. D radiodurans and T gammatolerans have multiple copies of their genetic data in their nuclei, using them to patch each other when they're damaged by radiation.
Much as Jeff Goldblum honestly annoys the ever-lovin' heck out of me, his character made a decent point in Jurassic Park. Life does find a way. It's an...elegant system, one not easily shut out. With enough pressure and enough generations for mutation to play out, evolution does crazy and amazing things. Fifty thousand mutants might not survive, but all it takes is one that does. Voila.