Altering humanity - what's the mental block about?

[GreyICE]

I've noticed the terraforming thread has gone on for pages about how we could spend vast amounts of resources to make planets and environments that are completely unsuitable for sustaining earth-normal life somehow habitable for us.

Isn't it infinitely easier to just use cybernetics and alterations to make humans who can live in those environments?

[Trolldor]

No.
You'd have to do it repeatedly for each human, presumably under the guise of a commercial venture which would restrict indefinitely.

And then there's the whole 'technologically feasible' aspect.

[GreyICE]

No.
You'd have to do it repeatedly for each human, presumably under the guise of a commercial venture which would restrict indefinitely.

And then there's the whole 'technologically feasible' aspect.

Ah, so the argument that current technology must resemble future technology despite what math and science have told us is possible?

We know many things about our body. For instance, the carrying capacity of oxygen of an engineered blood cell would hit a theoretical maximum limit of about 236 times what the current carrying capacity is. Dumping 15 ccs of engineered blood cells into the body would have a reasonably dramatic effect on our metabolism.

We have enough bleeding resources to outfit most of the humans in America with an automobile and we can't give some people 15ccs of engineered blood? I don't think so. This stuff will become quite easy enough.

P.S. What's the big deal about the commercial venture? Is Terraforming going to be egalitarian and socialist? If so, why not improving humanity (a much nobler and more useful goal, imho)? If they're both going to be commercially driven, what's the complaint?

[Trolldor]

The complaint is that companies would be paid by Governments etc. to terraform (can't believe I'm actually typing this sentence) while the cost of 'engineering' would fall to individuals.
Considering not all households can afford the goddamn internet yet...

Also, again, not technologically feasible - refer to: Temperature.

[GreyICE]

Temperature? The human body generates heat. Human body temperature is a function of heat generated and heat rejected by the body.

Reduce the heat rejected, internal temperature rises. Easiest thing in the world, we've been doing it since we lived in caves.

[Trolldor]

...enough to reject the "-" temp on Mars?

K.

[GreyICE]

...enough to reject the "-" temp on Mars?

K.

Of course. We generate heat, we simply have to reduce the rate rejected or increase the amount of heat generated until the temperature stabilizes at the level we like. Hotter temperatures make it much harder to reject heat, but colder temperatures just mean more insulation.

I mean space is bloody cold if you measure the temperature, but the biggest problem in space suits is overheating. There just isn't enough medium in space to reject heat into easily. Mars lacks that problem.

[Trolldor]

Ok, so how?

[GreyICE]

Ok, so how?

There's three modes of heat rejection, conduction, convection, and radiation. Conduction is irrelevant here, so we examine convection and radiation.

There we find two nice things. First, the density of the martian atmosphere is much, much lower. Lower density lowers the Rayleigh number directly. Also, lower gravity, and thus lower Rayleigh number. Since these are both first order, we can just do a direct comparison. Earth = 1 bar and 1 g, 288 K average, mars = 0.007 bar, 0.38g, 210 K average. Human body temperature is 310 K. So delta on earth is 22K average, delta on mars is 100 K average.

So convection heat transfer is 82 times higher on earth. Convection is typically the driving factor on a windy day, but it's somewhere around 0.7 of radiation on a still day, meaning it just dropped off the map.

So, radiation drives everything. Basic calculations are P = S-B Constant * e * A * T^4. 2 square meters is a good rule of thumb for human body area. The losses are 765 W, roughly. The human body produces 115 W roughly. So that gives a desired emissivity of 0.15 (rather than the lousy 0.97 of our skin). We quickly see that commercial aluminum has a emissivity of 0.09, and many metals are lower:
http://www.engineeringtoolbox.com/emiss ... d_447.html

So we'd need an aluminum mixture coating for our skin, or iron. They're both reasonable.

[Trolldor]

...and what about the brain?

[normal]

This is crazy talk! Why wasn't I invited!?

[JimC]

Virtually every piece of technology we have alters our ability to deal with environmental challenge.

Or we change our environment to suit.

Either way, it is clever hands, and clever hominid minds. I prefer us to stay the hominids we are, but to ramp up our supporting technology as far as it takes to get the job done...

[Clinton Huxley]

I suspect there is a little more to Marsifying a human than a few spoonfuls of super blood and a coating of bacowrap.

[Rum]

I suspect there is a little more to Marsifying a human than a few spoonfuls of super blood and a coating of bacowrap.

..not forgetting that delicious coating of chocolate!

[Clinton Huxley]

I suspect there is a little more to Marsifying a human than a few spoonfuls of super blood and a coating of bacowrap.

..not forgetting that delicious coating of chocolate!

Om nom nom!