On Fri, 18 Nov 2011 06:29:33 +0800, Robert Bannister <
rob...@bigpond.com>
wrote:
I believe that 'it would require' is overtating the situation. Let's
consider what it would take to make Venus and Mars habitable for Earth
humans.
Venus gets a pass on what I would consider the biggest hurdle, the
mass/gravity. It's already close enough to Earth's so that it isn't a
problem. The big problems with Venus are the atmosphere and the geothermal
activity. The problem with the atmosphere is just too darn much carbon and
not enough hydrogen. There's also rather more sulpher in the atmosphere
than we'd like to end up with. The solution would probably involve
nanotechnology but the real thing, not the sf 'magic wand' substitute.
Basically we would need to design and mass produce tailored extremophile
bacteria which would be seeded into the atmosphere and onto the surface to
fix sulpher into something less problematic tha sulfuric acid (sulpher
dioxide) which is currently the third larges compenent in Venus' atmosphere
(a distant third, but still). The bacteria seeded to the ground would be
disigned to 'eat' carbon dioxide and fix carbon into the planetary surface
with the mid-term goal of kick-starting the carbon cycle.
Another problem is Venus virtual lack of a magnetosphere, even though its
core should be roughly the same composition as Earth's (it can't be too
different or the mass/density of the planets wouldn't match so closely). An
allied problem is the planet's lack of rotation (there's probably a
chicken/egg question involved here). To work on these two problems
probably will require a more macroscopic approach than microscpic. The
first, and least theoretical approach is the brute force of controlled
planetary bombardment with asteroids.
Note that none of the above requires a new understanding of the laws of
physics or chemistry, or an ;understanding on 'how' that we don't currently
have (there's a difference, of course, in understanding how to do
something, and actually being able to do it). Basically all the above is
engineering, not theoretical physics.
Mars adds the gravity problem, ;which is more problematic than anything
we'd need to do with Venus. My engineering solution there is to
build/delve guide shafts at both poles and then send Very High Speed
meteors with a concentration of radioactive isotopes into them, basically
to build up the core, both in mass and in composition. This would likely
take longer than terraforming Venus atmosphere. Still, it doesn't require
re-thinking any laws of physics, just attacking an engineering problem with
adequate resources.
Again, terraforming Venus and Mars doesn't require readica changes in the
laws of physics, just long term and resource-expensive engineering projects
(likely to take a couple of hundred years for either planet, maybe more).
--
I must not fear. Fear is the mind-killer.
Fear is the little-death that brings total obliteration.
I will face my fear. I will permit it to pass over me and through me.
And when it has gone past I will turn the inner eye to see its path.
Where the fear has gone there will be nothing. Only I will remain.
(Bene Gesserit)