Is Laythe Actually Possible?

[SirSnuggles]

I assume not because there is are these barren planets all around them & it is so far from the sun.

[Mitchz95]

Many scientists believe the real-world moon Europa could possibly have a liquid ocean beneath its surface layer of ice due to tidal forces from Jupiter. So it's certainly possible for a moon to harbor life, even that far out from the sun. That said, Laythe would probably be subject to a lot of radiation.

[Stargate525]

Aye. And Saturn's moon, Titan, has an atmosphere that is thicker than ours. Laythe has always struck me a mixture of Titan and Europa. Possible, and considering the number of gas giants we've found among the exoplanets, I'd hazard to say that there is a similar moon out there somewhere.

But indeed, probably glowing with ionizing radiation.

[jwenting]

And who says there's life on Laythe? Just because there's what looks like water and it's liquid doesn't mean there's life...

The high radiation environment might make life more likely though, though it'd probably never evolve very far because the mutation rate would not be nice to multi-cellular organisms.

[SSSPutnik]

If it had a magnetic field it may be OK?

[FITorion]

The short answer is: Yes.

In our own system Europa could be just like Laythe if it were only a touch warmer. There are other sources of heat than the Sun.

[Dante80]

I assume not because there is are these barren planets all around them & it is so far from the sun.

http://en.wikipedia.org/wiki/Tidal_heating

[thiosk]

Maybe one of these should be stickied because the question comes up so frequently

I hope later updates do put lifeforms on the moon, and add a series of biome related sample return missions.

Would make for good SCIENCE

Edited December 10, 2013 by thiosk

[MalfunctionM1Ke]

Sorry for dropping this here but I wanted to point OP's Eyes on something:

As you see below, Laythe has almost the Gravity of Earth but only a Fraction of its size. I am no Geologist but out of what kind of matter must a Celestial body made of to create that much Downforce?

Of Course this is just a Game and OP is probably asking if there could be analoges to laythe out there in space.

My guess is maybe.

We see that Io is heated up by the tidal forced around Jupiter and therefore it has a very unexpected high vulcanism.

AND there is also Europa which shows many signy of Cryovulcanism, also induced by the tides of Jupiter.

So it is not just the Sun that melts water, it is also the Environment in which the Planet/Moon is in, Plus it's inner components (Radioactive materials for example)

[kahlzun]

And who says there's life on Laythe? Just because there's what looks like water and it's liquid doesn't mean there's life..

Oxygen atmosphere. Something has to be 'breathing' oxygen, since left to its own devices oxygen will eventually corrode everything on the surface, until there's no oxygen left.

Think of oxygen as a very slow acid.

It's possible some unknown procedure is generating the oxygen, but its one of the strange situations where 'alien life' is the simplest explanation.

[Stargate525]

As you see below, Laythe has almost the Gravity of Earth but only a Fraction of its size. I am no Geologist but out of what kind of matter must a Celestial body made of to create that much Downforce?

Considering that Kerbin, I believe, has the density of lead...

the funny thing about spheroids and gravity is that you actually need a rather large mass increase to get a noticeable gravity change, assuming the same or similar density. Smash two earths together and you don't get 2 gees at the surface. You get something around 1.07.

[Kasuha]

Short answer: no

Long answer:

Assumptions: Kerbin is in the Sun's habitable zone. Oceans on Laythe are made of water. Atmosphere is made of breathable mixture containing oxygen.

Laythe is 5 times further from Sun than Kerbin and with 25 times less Sun radiation is therefore definitely out of habitable zone. Tidal forces from Jool can keep its core heated up and can lead to volcanism keeping the average temperature in "habitable" levels but volcanoes are local surface phenomenon and with its thin atmosphere there is no chance it would be able to hold that heat long enough to be distributed evenly all over the surface. While it may seem wide, the 0-100 degrees range for the water to remain liquid is rather narrow. On real tidally volcanic planet surface the water would be mostly in two states: vaporized in near vicinity of volcanoes, and frozen everywhere else. Water vapor might help keeping the atmosphere greenhouse effect high, but definitely not high enough to allow liquid water over most of the surface. And overheated steam would have tendency to escape the planet into space, gradually drying the planet.

You guys argue with Io and Europa, but fail to notice that even volcanic Io has average surface temperature way below freezing (90-130K, i.e. -183 to -143°C) and Europa has (likely) liquid water ocean hidden under surface only because it is insulated by thick layer of ice. Ice is rather efficient thermal insulator.

Let's just enjoy the game. It would be a lot less fun if it was too realistic.

[Brotoro]

Could Laythe exist in our universe? No. It's density is 2.5 times the densest element known. You can come up with science fiction explanations for such a huge density, but there is no known way for it to happen naturally in our universe with our physics.

If you are asking if a real-life Jovian could have a large moon with a liquid water ocean and very substantial atmosphere, then I think it would be plausible. But such an object would not be the Laythe in our game.

If you want to accept some explanation for how Laythe can be so dense (to match what we observe in the game), then I think we could make Laythe-as-we-see-it in the game. The tidal heating in the Jool system with be much greater than it is in for the moons of Jupiter (because the distances between Jool and its moons are so small) so there could be plenty of heat generated. Also, Laythe's atmosphere is not "thin"…it's 0.8 bar… so it can help hold the heat. And I would expect the vast majority of Laythe's volcanoes to be underwater, simply because its surface is mostly ocean (and once a volcano grows an island on top of it, I would expect the heat to flow out by easier paths rather than through the thicker area of the island). So there will be a LOT of heat being dumped into the ocean that can keep it warm.

[Nano606]

If it had a magnetic field it may be OK?

It would have to be a massively strong magnetic field - many times higher than Earths. The gas giants simply put out way to much electromagnetic radiation in the direct area around them.

Bit of useless trivia: If they had not done the Pioneer missions prior to sending Voyager it would have been fried by the time it reached Jupiter and we would have had no further contact with it. Pioneer found there was way more radiation than they had expected, and Voyager was a more complicated probe that would have been killed had it not been fitted with the extra shielding added after the pioneer results.

[Kasuha]

Also, Laythe's atmosphere is not "thin"…it's 0.8 bar… so it can help hold the heat.

If Laythe had a Venus kind of atmosphere (92 bar surface pressure at 8.8 m/s surface gravity; notice it's not breathable mixture), it would still have hard time to hold the heat generated by volcanism and keep oceans liquid. You guys just can't imagine how much energy does sun deploy on our surface to keep our oceans liquid. Tidal volcanism is not anywhere near that. The difference is many orders of magnitude.

Hiroshima atomic bomb is estimated to have released 67 TJ of energy. Solar irradiance on Earth averages about 1366 W/m2. This means energy deposited by sun every day (approximating the day cycle by 8h direct irradiation) over each approximately 2 km2 of surface is roughly equal to one Hiroshima atomic bomb explosion.

For better comparison, to deliver the New York city (17,405 km2) its average temperature, there would be needed 10,000 Hiroshima atomic bomb explosions every day to deliver the same energy as sun does.

[S4qFBxkFFg]

My explanation for the enormous densities in the Kerbolar system is that it formed in a part of space where interstellar gas and dust coalesced around fragments of a shattered neutron star - it'll do as long as I don't find out it's impossible...

[SlyReaper]

http://en.wikipedia.org/wiki/Tidal_heating

Doesn't work. Laythe's orbit is perfectly circular, and is tidally locked to Jool. The only possible tidal heating would be via interactions from the other moons, which would be incredibly weak. Nowhere near enough to warm up Laythe.

[KvickFlygarn87]

http://www.youtube.com/watch%3Fv%3DfpaQpyU_QiM&sa=U&ei=DP2mUp_ZMoGNrQee7YAo&ved=0CAsQtwIwAA&usg=AFQjCNEYmT4FBbT_TKp-qH-8hHwtK2YZPw

[jwenting]

Oxygen atmosphere. Something has to be 'breathing' oxygen, since left to its own devices oxygen will eventually corrode everything on the surface, until there's no oxygen left.

Think of oxygen as a very slow acid.

It's possible some unknown procedure is generating the oxygen, but its one of the strange situations where 'alien life' is the simplest explanation.

depends on what the rest of Laythe is made from... And there are other processes that can decompose oxides, apart from photosynthesis. There's no need to involve life there at all.

[Kasuha]

And there are other processes that can decompose oxides, apart from photosynthesis. There's no need to involve life there at all.

I wouldn't have any problems with photosynthesizing life on Laythe if it was able to keep its temperature.

But I am curious which particular non-biologic processes do you have on mind which would be able to maintain oxygen atmosphere.

Because all matter used to compose planets comes from supernova explosions and elements in them come in certain proportions which give oxygen more than enough chances to get involved in covalent bonds before the planet forms.

Edited December 10, 2013 by Kasuha

[SRV Ron]

It would have to be a massively strong magnetic field - many times higher than Earths. The gas giants simply put out way to much electromagnetic radiation in the direct area around them.

Of course, there is the fictitious Pandora.

http://james-camerons-avatar.wikia.com/wiki/Pandora

[brdavis]

(Forgive me for what follows; I’m a physicist who teaching 100-level planetary science, so... yeah, these conversations resonant with me. The pun is coming.)

Let's just enjoy the game. It would be a lot less fun if it was too realistic.

I’d agree, but have to add applying rigorous science... to a game where the planets are made of unobtanium, denser than all known materials, and is based on a star that can’t exist... well, rigorous physics probably isn’t going to help resolve the question

Assumptions: Kerbin is in the Sun's habitable zone. Oceans on Laythe are made of water. Atmosphere is made of breathable mixture containing oxygen. Laythe is 5 times further from Sun than Kerbin and with 25 times less Sun radiation is therefore definitely out of habitable zone.

Yep, excellent analysis. At Laythe’s distance it is receiving 1/25th the solar energy as at Kerbin’s distance: Kerbin receives a *surface* average of 343 W/m^2 (not, actually, the 1370 W/m^2 that’s been thrown out there - that’s the intensity at 1 AU from the Sun, but a planet absorbs that over not its whole surface, but only its cross-sectional area; that throws in a factor of 1/4th). Laythe would then receive about 14 W/m^2 (again, averaged over the entire surface). In order to get the same amount of heating as Kerbin, Laythe would seem to need at least 329 W/m^2 additional. Tidal heating? Well... Io, the most tidally heated object we’ve got as an analog, produces 2.5 W/m^2 global average. So... Is Laythe a minimum of 130 times as tidally heated as Io? I have my (extreme) doubts. Furthermore that 0.8 Atm isn’t going to help much... not as much as the 1 Atm on Kerbin, for example. Greenhouse effect can help... but not that much.

You guys argue with Io and Europa, but fail to notice that even volcanic Io has average surface temperature way below freezing (90-130K, i.e. -183 to -143°C) and Europa has (likely) liquid water ocean hidden under surface only because it is insulated by thick layer of ice.

Got it in one, Mr Garibaldi .

My explanation for the enormous densities in the Kerbolar system is that it formed in a part of space where interstellar gas and dust coalesced around fragments of a shattered neutron star - it'll do as long as I don't find out it's impossible...

Neutron star matter isn’t stable at normal pressures. Don’t read this, you’ll find out it’s impossible. Oops .

Doesn't work. Laythe's orbit is perfectly circular, and is tidally locked to Jool. The only possible tidal heating would be via interactions from the other moons, which would be incredibly weak. Nowhere near enough to warm up Laythe.

That’s a good point, but I think it’s worth pointing out that the developers got this right - tidal heating in a Galilean resonance* means those orbits *can’t* be circular... but the very small dynamically excited eccentricity does result in significant tidal heating even through the orbits appear very very close to zero. Io has an eccentricity of 0.0041. That’s something like an order of magnitude smaller than any listed KSP eccentricity (I think?), so I’d say you can easily assume Laythe has an eccentricity... just one small enough you don’t bother modeling it.

...probably glowing with ionizing radiation.

Note that while a magnetic field is very handy, an atmosphere is a *great* shield. A breathable atmosphere will probably shield you from radiation here just fine (at least for as long as it lasts**)

Oxygen atmosphere… It's possible some unknown procedure is generating the oxygen, but its one of the strange situations where 'alien life' is the simplest explanation.

There is an important exception - given a planet that is entirely water (little to no rocky core at all, but overwhelmingly dominated by water), you actually would expect an oxygen atmosphere in some circumstances. UV splitting of H2O will give you an extremely oxidizing environment if the planet is small enough that H2 can escape, and with no significant reduced surface materials to oxidize... the O2 builds up. And up. And up. The result would be an interesting world... the water would end up with a lot of things like peroxides in it in potentially pretty significant concentrations. Want to watch your boat dissolve due to the water while potentially burning like a magnesium flare under a high-pressure pure oxygen environment? That could make an interesting world for boating Kerbals .

*that was the pun. Got it? Yeah, it’s a stretch***

**because let’s face it, we haven’t even touched[/] on atmospheric lifetimes here

***â€Âa stretchâ€Â. See what I did there?

PS- At what point should this end up in “Science Labs�

[numerobis]

It's not clear that Laythe's oceans are water; it could be something that's liquid at a temperature that makes sense for Laythe to have.

If it were hydrocarbon seas, it would suck the first time that Jeb throws a fag into the pond, and then the whole planet bursts into flame.

[Stargate525]

Okay, hold on.

Laythe, as it is in the game in every respect, is clearly impossible. It's neutron-star dense, so that's its kill right there.

But!

Is a habitable moon around a gas giant possible?

Is liquid water that far out from a goldilocks zone possible?

Is a moon that's not super-radioactive around a gas giant possible?

If you take not Laythe EXACTLY, but what it represents (A semi-earth analogue orbiting a gas giant), is it possible? I'd argue yes. Especially since a great majority of the gas giants we've found outside our system are much, much closer to their suns.

[Requiem762]

And who says there's life on Laythe? Just because there's what looks like water and it's liquid doesn't mean there's life...

The high radiation environment might make life more likely though, though it'd probably never evolve very far because the mutation rate would not be nice to multi-cellular organisms.

A lot of people suspect lay hates oceans are liquid ammonia.