> I perceive space migration as a vital step in
> human survival, and the faster we can migrate, the better.
Why do you say this? Please justify.
It takes ~11 days to dismantle Mercury and harvest the entire power output of the sun (using some reasonable assumptions like 1 kg/m^2 solar panels). Once you have that much power, dismantling everything but Saturn & Jupiter takes ~12 years (which take ~60 and 600 years respectively if you use all the available power).
If we assume nanotechnology develops ~2020, then we will have restructured much of the solar system before 2100. That is long before anything other than a nanoprobe would be able to migrate to any nearby systems. Given NASA's current approach (and almost universal head-in-the-sand with regard to really understanding Nanotech), I would predict that there may be one or more probes designed and launched to explore different bodies in the solar system that find their target is "missing" when they arrive. [This is a variant on the problem of launching a world-ship between stars when a world ship constructed with later technologies would end up getting there sooner.]
A re-engineered solar system is "virtually" indestructable (short of such "accidents" as stellar collisions or black hole encounters). So, if you believe that nanotech is feasible, and really want humanity to survive, then there are 2 things you should primarily support: (1) The near-Earth crossing object survey efforts and possibly the
development of (robotic) spacecraft that could nudge them out
of the way as far away as possible. The main reason for this
is to give us a "fighting" chance for survival should the very
low odds of a planet-killing object encounter in the next ~50
years be against us.
(2) Putting every other additional dollar of funds into the development
of nanotechnology. This means *no* manned missions and *no* Mars
missions. There could be some justification for space observatories
and things like the anticipated Mercury surveyor mission (should it
survive any budget cuts).
> Plus, the abundance of resources in space (once we start exploring in earnest)
> will help stimulate the very technologies that will allow for the kind of
> transhumanist habitat you envision.
The development of nanotechnology eliminates entirely the need for space based
resources for probably thousands of years (unless you can predict some kind
of population explosion). The doubling time of nanotech based power harvesting
and mass manipulation provides more that sufficient resources for very
comfortable living here on Earth without having to risk the hazards of space.
Only if you argue strongly for uploading and freedom for relatively endless
copying/mental-expansion do you need to go into space.
> I think sending ourselves into space, cumbersome meat and all, will ultimately
> accelerate our transition from biological to postbioligical...and I wonder a
> the possibilities of nanotech in microgravity!
This sounds like the argument of someone who waxes romantic at the idea of anything in space who doesn't really understand nanotechnology development and economic investments. The last time I checked, I was under the impression that each space shuttle flight was costing ~$400 million (someone correct this if they have better data). As pointed out in the nanoassembler thread, a semiconductor [nano]-fab would cost about a billion $. So cut 2-3 space shuttle missions and you have a state-of-the-art nano-development facility. A single shuttle mission would fund about ~2500 full-time scientists working on nanotech.
Fundamentally, (old-style) space activity involves "big-stuff" and is expensive because you have to manipulate lots of material. Nanotech research is much cheaper because it involves manipulating much less material (though the required precision is much greater). There is some hope regarding the NASA efforts for smaller/faster/cheaper but it is going to take the deaths of the "old-school" manned-mission proponents to stop the money pit activities.
[Just FYI, I'm a very romantic space-type myself and my eyes go all misty when watching things like Apollo 13 or the moon-landings, but I don't let my romanticism interfere with the logic of the the fastest way to achieve development and give the largest number of people the greatest amount of freedom with regard to the quality of their lives.]
Robert