Terraforming Venus

[Null]

@Lumpkin: Mars doesn't have a global magnetic field.

[N36fSL3A]

Well take a look at Venus - it's fine, and it has no magnetic fields.

[ResidentBiscuit]

Define 'fine'. Fine as in the planet is still solid? Sure. Fine as in able to support anything? Not quite.

And I think Venus actually has a very weak magnetic field

[13bSLyTq]

Venus isn't fine in terms of ability of sustaining life.

[lockandstrike]

I believe Lumpkin was trying to say that even presented with the non-existence of a magnetic field Venus has been able to sustain an atmosphere.

I believe this might come from the fact that provided with such a thick atmosphere a massive amount of energy and long time period would be required for this to be harmed. And when I say a "long time period" I'm talking about millions if not billions of years.

[N36fSL3A]

^This.

[Garion]

There should still be a means to calculate (estimate) how long an man made atmosphere on mars would last.

Even the earth's atmosphere is slowly leaking away. There isn't some bubble surrounding the earth where the atmosphere just stops.

[sargon94]

On the subject of plowing an asteroid into Mars, I don't think it matters where you hit. Ideally you'd want to hit the poles but the resulting dust ejection into the atmosphere from hitting anywhere else would raise temperatures enough to begin melting the poles anyway.

Frankly, I don't see the allure of colonizing other planets. Terra-forming would certainly be ludicrously expensive (perhaps prohibitively so), and ultimately creating spinning cylinders in space just sounds more reasonable. The spin creates whatever gravity you like (thereby eliminating problem no. 1), and the controlled environment eliminates the need for atmospheric engineering.

However, since this isn't subject, another way to terra-form Mars (other than asteroid golf) would be to nuke the poles (though this would create fallout, but only for a limited time). An even better (though slightly out of reach) approach would be to dump fusion reactors in the poles, the heat generated could melt them while simultaneously power on-surface research stations!

EDIT: typos

[Mats]

Energy given out by fusion reactors or nuclear strikes pale in comparison to the energies given off in asteroid impacts.

The impactor had an estimated diameter of 10 km (6.2 mi) and delivered an estimated energy equivalent of 100 teratons of TNT (4.2×1023 J).[22] By contrast, the most powerful man-made explosive device ever detonated, the Tsar Bomba, had a yield of only 57 megatons of TNT (2.4×1017 J),[23] making the Chicxulub impact 2 million times more powerful. Even the most energetic known volcanic eruption, which released an estimated energy equivalent of approximately 240 gigatons of TNT (1.0×1021 J) and created the La Garita Caldera,[24] delivered only 0.24% of the energy of the Chicxulub impact.

-Wiki

That's the kind of impact size that can start to terraform.

[lockandstrike]

The need to eventually find ourselves a 2nd home can be taken as fact because looking through the human growth in the last century I believe the planet will overflow with human population before the 23rd century. You might say 200 years is not enough time for this to happen but looking through the growth of population we can see a standard. Every 30 years the global population duplicates. Right now we have about 7 billions people. If this rule maintains in 2040 we will be 14 billion, in 2070, 28 billion and so on so fort.

So I believe that when we do possess technology to terraform an ENTIRE planet we will most likely also possess technology that will allows us to travel to a planet much similar to our own preventing us to perform such difficult and expensive operations in planets that are not apt for us to live in.

[sargon94]

Right now we have about 7 billions people. If this rule maintains in 2040 we will be 14 billion, in 2070, 28 billion and so on so fort

No, that's not how it works. When looking at population growth one must look at 3 things: total population, population growth (1st derivative), and the 2nd derivative (the growth of the growth).

Currently, our population is >7 billion, is growing, but the rate at which it is growing is negative (and falling). Meaning: Our growth rate is dropping, and the rate at which it is dropping is increasing (that's the 3rd derivative). Conclusion: Eventual stabilization, probably between 10 and 12 billion. Mind you, that's still awfully crowded and we're going to need to some serious advances in gene-modded sustenance, but it's possible.

Second point: mass migration to other solar system (the only way to find a planet like ours) may be just a costly as creating one. When one considers the extreme cost of accelerating just one kilogram to .2c (a slow but reasonable speed for interstellar travel), and then multiply that by what mass-migration would demand, it would almost certainly require stripping the entire solar system of most resources. So, while it's definitely possible, it'd be a much better idea to move our entire civilization to the stars. Become Homo Astrum as it were.
EDIT: typos

[Mats]

0.2c is far from reasonable. It's totally unachievable.

[sargon94]

0.2c is far from reasonable. It's totally unachievable

Not at all, several solar sail/beamed laser combinations estimate maximum speeds of .5c.
http://en.wikipedia.org/wiki/Interstellar_travel

For those who are interested, I also recommend reading Physics of the Future by Michio Kaku, an extremely good view of the what the next hundred years might offer.

EDIT: In the book he describes terra-forming in great detail (on Mars, he seems to agree that Venus is not a suitable candidate). Also, I strongly recommend looking into Europa (the moon). Beneath the ice there's a massive liquid water ocean, and it's possible there may be life there (perhaps extremophiles living off ocean floor gas vents).

[N36fSL3A]

And risk killing possible life under the surface?

The best bet would be to try to get one of it's volcanoes active - Assuming that the core of Mars isn't actually frozen.

[sargon94]

And risk killing possible life under the surface?

lol wut? My bad... I meant for research, or simply curio, not terra-forming. Europa is actually a planet you would want to settle as is (live in the ice) due to the fact that the ice would shield you from Jupiter's intense radiation (think Van-Allen Belt but 10x more powerful). Standing on Europa's ice will reward you with a lovely 540 rem :D

I wouldn't dream of potentially harming life there (if it exists). I think the distance from the sun and absolute lack of atmosphere would make terra-forming nigh on impossible right? Also I seem to remember Jupiter's massive gravity as being an issue of some sort.

[N36fSL3A]

I was replying to the 'nuking' comment.

Europa seems nice, but most life would probably be underneath the surface.

[Garion]

Europa is much harder to get to than Mars. We don't even currently have rocket tech that can take us directly to Jupiter in a reasonable time.


Just look at the Cassini probe as an example of how hard it is to get something to Jupiter (I know Cassini was headed to Saturn but it got a gravity assist from Jupiter also). The probe needed multiple gravity assists from planets.

Mars really is the only thing some what plausible to send people to at the moment. (Mars is something like 35 million miles. The distance to Jupiter/Europa would be something like 400 million miles)

Although I do kind of question the usefulness of sending people to Mars. Who knows though, maybe those Mars One people will actually pull it off and find something interesting.

[htirwin]

I've always thought that terraforming will likely be doable though either very sophisticated systems of intelligent self replicating "robots", or some form of genetically engineered life, or a combination. It may also take quite a long time, and of course a lot of energy, but this is not something we need to worry about because it will be energy harvested by our workers. Ideally we would need very little interaction with them once they get going.

[Cody0023]

Well mars doesnt even have a magnetic field so unless we can heat up the core,spin it and create convection in the lower layers we cant even talk about an atmosphere lol

[N36fSL3A]

So you didn't read anything from above. As stated there, Venus has a very weak magnetic field, and it has a monstrous atmosphere. Why can't Mars be similar? Not to mention it HAS a magnetic field.