Would Laythe really be habitable, Redux

[Brotoro]

And that is where I disagree. From what I understand that would basically need the surface to be so hot that it has basically turned into liquid. Also there is not much surface to talk about either. The water just would have evaporated if there was anything on the planet generating that much heat/energy.

How can you disagree? The Earth gets along just fine with that average heat energy impinging on its surface, so why would the surface of Laythe (and I include all the surface, even under the oceans, not just on the islands) have to be molten under that same average daily heat flow condition? The surface of Laythe wouldn't even have to withstand the greater heating spikes that the Earth's surface does when it gets bombarded with over 1000 watts/sq.meter at times...Laythe's crust just deals with the steady outflow of a few hundred watts/sq.meter.

[Brotoro]

That might also explain the EVA report. If Laythe's atmosphere is something like 5% kerbon dioxide, it could create a greenhouse effect, be toxic and have an acceptable level of oxygen all at once.

Is 5% carbon dioxide toxic to kerbals? We don't even know what the composition of Kerbin's atmosphere is (except that it contains substantial oxygen, since jet engines work fine there).

Edit: Ah! You are referring to the EVA report? Yes, that could be because of high carbon dioxide levels.

Edited November 13, 2013 by Brotoro

[boxman]

How can you disagree? The Earth gets along just fine with that average heat energy impinging on its surface, so why would the surface of Laythe (and I include all the surface, even under the oceans, not just on the islands) have to be molten under that same average daily heat flow condition? The surface of Laythe wouldn't even have to withstand the greater heating spikes that the Earth's surface does when it gets bombarded with over 1000 watts/sq.meter at times...Laythe's crust just deals with the steady outflow of a few hundred watts/sq.meter.

Because to get anything resembling that amount of energy with so little solar radiation would basically melt everything which is not the case with laythe. And if the interior core was so hot that it would lead to air temperature 4c there is no way any liquid would survive in liquid form.

There is big difference from getting 1000watts~ from a external source like the sun compared to interior heat caused by tidal effects.

If it was closer to duna orbit then I would have found it plausible, but for now it just seems completely inplausible from everything I have learned over the years of reading about these topics.

To me it is just completely unrealistic which is the same issue I have with frozen water ice being on minimus.

But I guess we will just have to agree to disagree.. This is why I kinda wish they didnt state that it was water, so that we could form our own conclusions based on what we believe it could be.

[FITorion]

If it was in the real world it would not even have liquid oceans. I have heard some people from squad talk about how it is heated by the tidal forces caused by Jool, but there is no way in reality that it would heat up the actual atmopshere to allow liquid oceans on the surface.

In real world it would be like Europa or the other moons around the gas giants that are believed to have a liquid ocean underneath the ice.

So if it was realistic it would have a ice cover with maybe an ocean underneath while still being very cold at surface.

It is the same thing with minimus.. It is said to have ice cover, but that makes no sense at all since it has no atmopshere. The surface temperature on a real moon like minimus would vary from extremely high temperatures on the sunlight side and extremely low during night time. The only places ice could exist in real world would be in deep craters that are always in the shade.

Europa doesn't currently have an atmosphere. It's far enough away from the Sun for ice to remain solid in a vacuum. If Earth's atmosphere would have a little different make up then Earth would be covered in ice. The greenhouse effect is very important to keeping us warm and not an ice ball.

Europa only needs to be a little warmer and the oceans would be warm enough to not have ice over the top anymore. Only a smidgen closer to Jupiter and it'd be there. There's a "Goldilocks" zone where the tidal heating would be just right. Not as hot as Io and just a little warmer than Europa and we'd have a Laythe like moon in out own solar system.

Exposed to vacuum the water would boil off some... and form an atmosphere of water vapor... Then comes the question of radiation... If there is just the right amount then some of the water vapor could be denatured into Hydrogen and Oxygen. Even our own gravity isn't enough to hold on to Hydrogen. It would get lost to space and leave a mostly Oxygen atmosphere behind. Water vapor is one of the stronger green house gasses. If the radiation wasn't too strong then a fair amount would also be present and you'd have a moderately warm surface.

Edited November 13, 2013 by FITorion

[RuBisCO]

Technically not true, the atmosphere is not dense enough to deflect solar radiation. The majority of the solar radiation is deflected thanks to the earths magnetic field. In fact if the Earth did not have it's magnetic field, much of the atmosphere would simply blow off because of the solar winds and we would be more like Mars.

If your technicality is a time scale of billions of years! Venus for example has no magnetic field and yet has an atmosphere of 91 times the surface pressure of ours. Mars lost it atmosphere because it gravity was to weak, if it had more gravity solar striping would have much less an effect. Again even if you we were afloat above the clouds of Venus during a solar flare you would be exposed to no radiation, the atmosphere is enough protection. This it not hard to calculate, for example there is 5*10^18 kg of atmosphere on earth (wiki), if that was water our atmosphere would be about 10 meters thick. According to this study we would need only 20 cm depth of water to defend us against the worse solar flare. As for cosmic rays the most powerful particles in the known universe, accelerated by supernovas that make Jupiter's magnetic field look like a fridge magnet, 5 meters of water shielding would stop them, or at least enough of them to liveable levels

[Commander Zoom]

Europa doesn't currently have an atmosphere. It's far enough away from the Sun for ice to remain solid in a vacuum. If Earth's atmosphere would have a little different make up then Earth would be covered in ice. The greenhouse effect is very important to keeping us warm and not an ice ball.

Europa only needs to be a little warmer and the oceans would be warm enough to not have ice over the top anymore. Only a smidgen closer to Jupiter and it'd be there. There's a "Goldilocks" zone where the tidal heating would be just right. Not as hot as Io and just a little warmer than Europa and we'd have a Laythe like moon in out own solar system.

Exposed to vacuum the water would boil off some... and form an atmosphere of water vapor... Then comes the question of radiation... If there is just the right amount then some of the water vapor could be denatured into Hydrogen and Oxygen. Even our own gravity isn't enough to hold on to Hydrogen. It would get lost to space and leave a mostly Oxygen atmosphere behind. Water vapor is one of the stronger green house gasses. If the radiation wasn't too strong then a fair amount would also be present and you'd have a moderately warm surface.

This right here, especially the last paragraph, is what I believe re: Laythe - including the explanation for how it can have significant amounts of free oxygen without life.

[Brotoro]

But I guess we will just have to agree to disagree..

OK.

To me it is just completely unrealistic which is the same issue I have with frozen water ice being on minimus.

Yeah, Minmus is a different problem. But they told me it was ice... and the only way I could come up with to reconcile this was to imagine that the early Minmus (still warm after formation from radioactive decay inside) had a species of microbes living in its oceans that secreted a resin that remains to this day in the ice of Minmus. When the ice of Minmus is exposed to vacuum, the water will indeed sublime into space...but the small fraction of resin gets left behind and forms a barrier to further sublimation. Also, the ice on Minmus will reflect away a lot of the incoming sunlight, so it will not get as hot as Kerbin at the same distance from Kerbol. (Our own Earth is at a distance from the Sun where its equilibrium temperature would be below the freezing point of water were it not for the greenhouse effect of our atmosphere jacking it up another 18 degrees C or so.)

[boxman]

Europa doesn't currently have an atmosphere. It's far enough away from the Sun for ice to remain solid in a vacuum. If Earth's atmosphere would have a little different make up then Earth would be covered in ice. The greenhouse effect is very important to keeping us warm and not an ice ball.

Europa only needs to be a little warmer and the oceans would be warm enough to not have ice over the top anymore. Only a smidgen closer to Jupiter and it'd be there. There's a "Goldilocks" zone where the tidal heating would be just right. Not as hot as Io and just a little warmer than Europa and we'd have a Laythe like moon in out own solar system.

Exposed to vacuum the water would boil off some... and form an atmosphere of water vapor... Then comes the question of radiation... If there is just the right amount then some of the water vapor could be denatured into Hydrogen and Oxygen. Even our own gravity isn't enough to hold on to Hydrogen. It would get lost to space and leave a mostly Oxygen atmosphere behind. Water vapor is one of the stronger green house gasses. If the radiation wasn't too strong then a fair amount would also be present and you'd have a moderately warm surface.

But if had the capability to pump so much heat into the atmopshere there is just no way that water could survive.

It is very different with heat/energy generated by a star since most of that energy will end up heating up the atmosphere with very little actually reaching the surface. This is why atmosphere less moons like our own is so much hotter on surface even though it is at same distance from sun.

And no matter how hot much heat is generated on inside it would still freeze on top when it is exposed to extremely cold air temperature or lack of it which is the case with Europa. Even if the water is near boiling hot underneath the ice there would still be some kind of ice sheet ontop due to those low temperatures.

Even if we somehow moved a planet with very high atmospheric pressure and loads of greenhouse gases like venus it would still eventually cool down due to lack of external energy coming in. There is just is no goldilocks zone when it comes to liquid surface water that far from the star.

[boxman]

OK.

Yeah, Minmus is a different problem. But they told me it was ice... and the only way I could come up with to reconcile this was to imagine that the early Minmus (still warm after formation from radioactive decay inside) had a species of microbes living in its oceans that secreted a resin that remains to this day in the ice of Minmus. When the ice of Minmus is exposed to vacuum, the water will indeed sublime into space...but the small fraction of resin gets left behind and forms a barrier to further sublimation. Also, the ice on Minmus will reflect away a lot of the incoming sunlight, so it will not get as hot as Kerbin at the same distance from Kerbol. (Our own Earth is at a distance from the Sun where its equilibrium temperature would be below the freezing point of water were it not for the greenhouse effect of our atmosphere jacking it up another 18 degrees C or so.)

No amount of albedo could stop that ice from vaporizing if there is no atmosphere to deal with all the incoming radiation. The surface on sunlit regions would still be very hot even if alot of it was reflected by the ice itself.

[Brotoro]

...It is very different with heat/energy generated by a star since most of that energy will end up heating up the atmosphere with very little actually reaching the surface.

That is not the case. On Earth, the atmosphere absorbs only about one quarter of the incoming solar radiation. Another quarter is reflected by the the atmosphere. About half reaches the Earth's surface, and most of that is absorbed (maybe 5% is immediately reflected by the surface).

[Brotoro]

No amount of albedo could stop that ice from vaporizing if there is no atmosphere to deal with all the incoming radiation. The surface on sunlit regions would still be very hot even if alot of it was reflected by the ice itself.

That is only an effect I was counting on the help. It's the resin that does the trick. "Wrapped in plastic...its fantastic."

[FITorion]

But if had the capability to pump so much heat into the atmopshere there is just no way that water could survive.

It is very different with heat/energy generated by a star since most of that energy will end up heating up the atmosphere with very little actually reaching the surface. This is why atmosphere less moons like our own is so much hotter on surface even though it is at same distance from sun.

And no matter how hot much heat is generated on inside it would still freeze on top when it is exposed to extremely cold air temperature or lack of it which is the case with Europa. Even if the water is near boiling hot underneath the ice there would still be some kind of ice sheet ontop due to those low temperatures.

Even if we somehow moved a planet with very high atmospheric pressure and loads of greenhouse gases like venus it would still eventually cool down due to lack of external energy coming in. There is just is no goldilocks zone when it comes to liquid surface water that far from the star.

The part in Red is completely wrong. I'm sorry but you need to go back to physics class if you believe that.

[Anton P. Nym]

Laythe if it has a magnetic field likely would be attached to Jools and radiation would stream into its polar regions making a continues aurora.

Which would be awesome to see in game... if Squad can fit it in somehow.

*cough*

-- Steve

[boxman]

That is only an effect I was counting on the help. It's the resin that does the trick. "Wrapped in plastic...its fantastic."

hehe

I rather just pretent it is made from something with really high melting point.

But each to their own

[Brotoro]

Aurora on Laythe would be cool:

[boxman]

The part in Red is completely wrong. I'm sorry but you need to go back to physics class if you believe that.

I think you missed the part about the amount energy required to heat the atmosphere to 4c~. To melt the ice on top it literally would have to be above boiling when exposed to such extremely cold temperatures that you would find on a real moon at that distance from the sun. If it is that hot, then the oceans would evaporate if it was mater of anything that resembles water. The atmospheric pressure is even lower than that of earth, which means it would boil of even faster.

[boxman]

Which would be awesome to see in game... if Squad can fit it in somehow.

*cough*

-- Steve

Indeed... Would love to have aurora effects in kerbal space.

[Horn Brain]

Just a note about the radiation: if Laythe's atmosphere has roughly the same molecular weight as air, then the density at sea level is around 1 kg/m^3. If the scale height is 4km, then the mass shielding from the atmosphere is around 4,000 kg/m^2. That's equivalent to a few meters of water between life on the surface and the radiation, which would be a very effective shield, even against cosmic rays.

Additionally, life could exist under the oceans on Laythe for even more shielding. The tidal heating would likely result in volcanic activity and probably hydrothermal vents, which we know are good habitats for life on Earth and would be completely shielded from radiation. If more shielding were required than the atmosphere, then a submarine base for visiting Kerbals would only have to be something like 10 feet below the waves to provide very effective radiation shielding. The challenge would be in getting to and from Laythe.

As for the atmosphere being sputtered away by the radiation: That process occurs over hundreds of thousands of years. Healthy volcanic activity could renew gases lost to space just like it does here on Earth, and it might not even be necessary if Laythe's composition is like Europa, which has something like twice as much water as the Earth, despite having less than 1% of its mass. The atmosphere could be in a nearly steady-state as Laythe slowly loses light atoms to radiation which are replenished from the effectively inexhaustible supply at and below its surface.

Not all of the processes that would be necessary for Laythe to be "possible" are modeled in the game. There are no clouds, no volcanoes, etc. I think with some imagination (and some borked Kerbal physics along the lines of the 10x gravity constant/super dense materials), it isn't hard to imagine such a body being possible, at least within the game.

[FITorion]

I think you missed the part about the amount energy required to heat the atmosphere to 4c~. To melt the ice on top it literally would have to be above boiling when exposed to such extremely cold temperatures that you would find on a real moon at that distance from the sun. If it is that hot, then the oceans would evaporate if it was mater of anything that resembles water. The atmospheric pressure is even lower than that of earth, which means it would boil of even faster.

There isn't an atmosphere. You just need enough heat to get the ice to sublime and or melt and boil away to then create an atmosphere and thus atmospheric pressure to stop the subliming/boiling. Once you have an atmosphere then the heat from the sun can be trapped... There is still quite a lot coming from the Sun even out at Jupiter. You just need a green house effect to capture it and water vapor is one of the better gasses at doing that.

The main problem for Europa is the radiation environment and its lack of a strong magnetic field to counteract it. Things would have to be just right to get a Laythe but it is feasible for such a moon to exist.

[boxman]

There isn't an atmosphere. You just need enough heat to get the ice to sublime and or melt and boil away to then create an atmosphere and thus atmospheric pressure to stop the subliming/boiling. Once you have an atmosphere then the heat from the sun can be trapped... There is still quite a lot coming from the Sun even out at Jupiter. You just need a green house effect to capture it and water vapor is one of the better gasses at doing that.

The main problem for Europa is the radiation environment and its lack of a strong magnetic field to counteract it. Things would have to be just right to get a Laythe but it is feasible for such a moon to exist.

We were talking about laythe not Europa.. And if you read up on the subject you would find out that there is very little energy from the sun reaching the planets in outer solar system. No amount of greenhouse effect on a rocky/ice planet/moon will be enough to get anywhere near 0c in the outer solar system.

[Brotoro]

We were talking about laythe not Europa.. And if you read up on the subject you would find out that there is very little energy from the sun reaching the planets in outer solar system. No amount of greenhouse effect on a rocky/ice planet/moon will be enough to get anywhere near 0c in the outer solar system.

The greenhouse effect works by impeding the escape of infrared radiation from the surface. It doesn't matter WHERE the energy came from that made the surface warm...the greenhouse gasses will still impede the infrared energy's escape to space. So energy from tidal heating that works its way up out of Laythe's crust still has to contend with the greenhouse gasses, so the surface will be warmer because of it.

[FITorion]

We were talking about laythe not Europa.. And if you read up on the subject you would find out that there is very little energy from the sun reaching the planets in outer solar system. No amount of greenhouse effect on a rocky/ice planet/moon will be enough to get anywhere near 0c in the outer solar system.

Laythe is just like a Europa that's been warmed up a bit. Discussing what would happen if Europa was slightly warmer is discussing one possible way for Laythe to be the way it is.

[boxman]

The greenhouse effect works by impeding the escape of infrared radiation from the surface. It doesn't matter WHERE the energy came from that made the surface warm...the greenhouse gasses will still impede the infrared energy's escape to space. So energy from tidal heating that works its way up out of Laythe's crust still has to contend with the greenhouse gasses, so the surface will be warmer because of it.

You still dont get that the surface and core would have to be impossible hot to heat up the atmosphere to anything close to where ice melts into liquid water.

When it comes to atmosphere warming it matters alot.

When you have heat from sun it will heat up the atmosphere while the radiation/lightrays travels through the atmosphere with very little actually reaching the surface which is why the surface temperature on earth is comfortable instead of blistering 200c like our own moon.

If you get same amount of energy from the interior that same energy is used to heat up the surface and water instead of the atmosphere, which means it would be boiling off long before any significant heat is added to the atmosphere.

Even if the water was literally boiling from interior heat there would still would not be anywhere near the effect of the atmosphere heating our planet for example experiences.

Besides we are talking about a moon here with 85% the pressure of our planet. Atmospheric pressure has alot more to say than the percentage of greenhouse gases when it comes to being able to hold heat. But either way there is no way it could be heated up anywhere near enough to allow for liquid water at such a distance from the sun.

[boxman]

Laythe is just like a Europa that's been warmed up a bit. Discussing what would happen if Europa was slightly warmer is discussing one possible way for Laythe to be the way it is.

It has no atmosphere, so not comparable at all. And even if it had an atmosphere it would still not have any liquid oceans on surface.

It is just not possible no matter how much tidal forces there are.. It has to be closer to the sun for there to be any remote chance of that.

Even if it was moved closer to the sun that water would most likely eventually leak off into space anyways like what most likely happened to Mars after losing the magnetic field.

[DeathFromBelow]

It has no atmosphere, so not comparable at all. And even if it had an atmosphere it would still not have any liquid oceans on surface.

It is just not possible no matter how much tidal forces there are.. It has to be closer to the sun for there to be any remote chance of that.

Even if it was moved closer to the sun that water would most likely eventually leak off into space anyways like what most likely happened to Mars after losing the magnetic field.

Laythe's surface gravity is 0.8G, more than enough for a dense atmosphere, and I would assume that Jool's magnetic field would prevent oxygen/water loss. With tidal heating, internal heat from radioactive decay, and the correct chemical composition of the oceans I don't think its impossible for the ocean to exist.

Beyond that, we're dealing with an alternate universe with different physics anyway. All the objects in KSP are far too small/dense to actually wxist with their in-game properties.