Theorize Possible Colonization on Europa

[mrudis65]

I am writing an interactive fiction roleplaying game. It is futuristic... in fact centuries away. We have discovered that the core of Europa is indeed liquified iron, silicon (and sulphur gas?) The oceanic layer is indeed liquid water. Not only that, but it was discovered that a very thin layer of oxygen, nitrogen, hydrogen and other trace elements exists between the ocean and the outer frozen shell. To be determined is: whether there are fissures that release geo-thermal energy (heat) into the ocean. What would be the complications and implications of this?

First, where can I find the most recent data on the composition, known elements, temperature, etc... for Europa?

And second, in order to make my story compelling to scientists and physicists (I'm a mathematician) I would like input as to what a potential human colony might look like, given the scenario described. The storyline is not intended to be beyond the grasp of a non-scientist. However, I would like the descriptions of structures and habitats to be in the realm of theoretical possibility, however remote. Would there be volcanic activity? If so, how does one explain the smooth and non-punctured surface?

 

[pantechc70]

If you want this to be anything near realistic, the "shelter" the astronauts will live in has to be radiation proof. Europa is inside Jupiter's deadly radiation belt so that will be the biggest problem that your astronauts have to deal with. I can't say for sure what it would do to humans or their gear; but Europa only potentially has liquid ocean because of tidal heating from Jupiter stretching the surface. So if Jupiter's gravity can morph stone, what will it do to humans? You will also need to take into account that Europa is around 80 to 130 Kelvin ( around -300 to -225 Fahrenheit ).

 

[Nicodemus]

If you want this to be anything near realistic, the "shelter" the astronauts will live in has to be radiation proof. Europa is inside Jupiter's deadly radiation belt so that will be the biggest problem that your astronauts have to deal with. I can't say for sure what it would do to humans or their gear; but Europa only potentially has liquid ocean because of tidal heating from Jupiter stretching the surface. So if Jupiter's gravity can morph stone, what will it do to humans? You will also need to take into account that Europa is around 80 to 130 Kelvin ( around -300 to -225 Fahrenheit ).

Your gear, and the shielding would become brittle as it's bombarded by high energy neutrons and the like. If you can shield against that effectively, then fusion blankets are probably already a reality, and temperature extremes can be handled. The question would probably be: why Europa?

I think people forget just how BIG this solar system is compared to humans; we don't need to look so far to colonize, and certainly not next to a could-have-been-a-star.

 

[pantechc70]

Your gear, and the shielding would become brittle as it's bombarded by high energy neutrons and the like. If you can shield against that effectively, then fusion blankets are probably already a reality, and temperature extremes can be handled. The question would probably be: why Europa?

I think people forget just how BIG this solar system is compared to humans; we don't need to look so far to colonize, and certainly not next to a could-have-been-a-star.

I agree, Mars or even the moon would make much better colonies than Europa. If only because they aren't sitting inside a cloud of radiation. The only reason a colony on Europa would be useful is if we can confirm there is water underneath the surface. Which means it could possibly have life.

 

[Nicodemus]

I agree, Mars or even the moon would make much better colonies than Europa. If only because they aren't sitting inside a cloud of radiation. The only reason a colony on Europa would be useful is if we can confirm there is water underneath the surface. Which means it could possibly have life.

Which really... if it did have ET life, would be a reason to leave it undisturbed except for probes. It would be very imperial of us to colonize an irradiated and frozen hellscape just to disturb what might pass for local life. ;)

 

[pantechc70]

Lol yes, until we learn how to not contaminate everything we touch we can never investigate if there is life. If we sent a probe to Europa now we'd probably end up finding the bacteria we brought there.

 

[qraal]

I am writing an interactive fiction roleplaying game. It is futuristic... in fact centuries away.

Why not?

We have discovered that the core of Europa is indeed liquified iron, silicon (and sulphur gas?)

Io is believed to have a core of liquid Iron sulfide. Not sulfur gas.

The oceanic layer is indeed liquid water. Not only that, but it was discovered that a very thin layer of oxygen, nitrogen, hydrogen and other trace elements exists between the ocean and the outer frozen shell.

The Shell has to be in contact with the ocean - the pressure is too high for gas pockets. However, the ocean is very likely to have dissolved oxygen and peroxide from the radiolytic chemistry driven by Jupiter's magnetosphere's trapped particles striking the surface ice.

To be determined is: whether there are fissures that release geo-thermal energy (heat) into the ocean. What would be the complications and implications of this?

Depends. Europa's ocean/ice-shell is believed to be ~100 km thick. At the bottom the pressure is about ~1400 bar and in direct contact with the silicate interior. There has to be a lot of geothermal activity for an ocean to remain liquid. The important question is whether that means enough energy to power a vigorous biosphere. Lots of black-smoker like mineral outflows, perhaps, but beyond that...?

First, where can I find the most recent data on the composition, known elements, temperature, etc... for Europa?

Wikipedia is a good start, surprisingly. Then look at all the astrophysical journals. Best way to do that is via NASA's Astrophysical Database Server...

http://adsabs.harvard.edu/abstract_service.html"

And second, in order to make my story compelling to scientists and physicists (I'm a mathematician) I would like input as to what a potential human colony might look like, given the scenario described. The storyline is not intended to be beyond the grasp of a non-scientist. However, I would like the descriptions of structures and habitats to be in the realm of theoretical possibility, however remote. Would there be volcanic activity? If so, how does one explain the smooth and non-punctured surface?

Read some articles about Europa and you'll get a better picture. There's lots of material available. The crucial question is just how thick the ice is and Europa's present day outwards heatflow would have a lot to do with that. The estimates vary. Read widely and you'll see a broad range of opinions. But to give you a rough idea the super-volcanic moon Io is believed to have a geothermal heat-flow of about 3 W/square metre. Earth's is ~0.08 W/sq.m. Europa is somewhere in between. Call it 1 W/sq.metre. The surface temperature is about ~100 K. An ocean is at about ~277 K. That's a temperature gradient of ~177 K. Ice has a thermal conductivity of about 4 W/m.K, thus to reduce support a temperature gradient of ~177 K that 1 W/sq.m heat-flow needs an insulating blanket of 4 x 177 metres of ice, minimum. Europa's surface gravity is ~1.35 m/s^2, thus the minimum ice-blanket exerts about ~900 kPa on the ocean. "Warm" ice can undergo solid-state convection and that supports a shallower thermal gradient, meaning a much thicker ice-layer is needed. How much thicker? No one knows. Make an informed guess.

But that's average thickness. Tidal flexing over Europa's orbit can cause channels in the ice to open and close, thus a literal rising and falling of the ocean with the tides, perhaps by hundreds of metres. Some kind of photosynthesis might even be possible when the tide rises to its highest. Contrary to the gloomy statements by the other posters, the thickness of ice Life needs for radiation protection is trivial - less than a metre will do. And x-rays produced by high-energy collisions might provide another source of energy for an alien photosynthesis - even on Earth there's a fungus suspected to use x-rays produced by nuclear reactors for biochemical energy.

So go from there. I hope I've helped stimulate your imagination some more.

 

[Nicodemus]

Qraal, I was gloomy at the thought of what the original poster asked, which is colonization. I wouldn't attempt to speculate about exobiology, if it exist.

 

[mrudis65]

Thanks to all who replied. Very insightful. (If this were slashdot I'd give you 5 for insightful). I totally forgot about the radiation belt. That really puts a dampener on the whole concept. About colonization, I am in the "camp" that subscribes to the idea that Earth will eventually become uninhabitable and we will need to branch out if humanity is to survive.

Cheers.

By the way my story has taken a whole new twist. Alien yes. In our solar system. No.

 

[qraal]

Thanks to all who replied. Very insightful. (If this were slashdot I'd give you 5 for insightful). I totally forgot about the radiation belt. That really puts a dampener on the whole concept.

Really? It shouldn't. Any protection against Cosmic rays - with typical energies in the GeV range - will also protect against Jupiter radiation belt particles (with ~15 MeV peak energies.) To get to Jupiter space vehicles will automatically be protected against the rad-belts.

About colonization, I am in the "camp" that subscribes to the idea that Earth will eventually become uninhabitable and we will need to branch out if humanity is to survive.

Cheers.

By the way my story has taken a whole new twist. Alien yes. In our solar system. No.

Intriguing. The Larry Niven/Edward Lerner collaboration "Fleet of Worlds" features aliens on a Europa like moon, which develop a natural neural networking (mistaken for sex) enabling them to simulate experiments otherwise impossible in their aqueous home. Thus they develop means of venturing on to the surface and experiment with combustion and so forth.

As for the "uninhabitable Earth", while it's commonly imagined, that's only the end state of letting a bunch of natural forces dominate, rather than intelligently guiding them and engineering the planet for Life's benefit.