Not that I WANT to terraform Mars...

Such a ring would be structurally impossible. Even if we found some
magic material with that kind of strength, superconductors can't
really store as much power as everyone believes. The same magnetic
field that you are trying to create will cause decoupling of electrons
in the superconductor making it lose superconductivity. The magnetic
field for complete decoupling is not very high and is normally
measured in the micro-Teslas.

Consider the problem of active shielding in colonies and then scale it
up to planetary levels.

What most terraforming enthusist believe is that planets are easier to
work with, because they happen to live on one. In reality all the
problems associated with space colonization (except possibly gravity)
would have to be solved on a planetary level. This includes atmosphere
retention, passive and active shielding, temperature control,
maintenance and control of the biosphere.

Stop thinking of Mars as that planet over there ready to be colonized,
and start thinking of it as a very large colony that has to be
actively managed like any other complex none self-regulating system.

Most people dismiss timescales of geological eras, but is anyone sure
that the timescales required to create a self-regulating planet wide
system is significantly smaller. Life on earth is about 4 billion
years old, and for 3.4 billion of those years the highest life form
was blue green algea. What if it takes a million years for the
equivalent organism on Mars to get to a self-regulating stage that
allows more complex life forms to exist on the surface? Can human
interference significantly decrease the time, or are we simply
producing a system that has to be maintained and regulated by us for a
million years while that organisms do what it has to do to make Mars
habitable.

Finally even if we were successful in producing a self-regulating
bio-sphere on Mars, why is anyone so sure that humans would be able to
live there?

Bill
--- In spacesettlers@y..., "Dr. Omni" wrote:
> From:
> To:
> Sent: Wednesday, July 18, 2001 11:25 PM
> Subject: [spacesettlers] Re: Not that I WANT to terraform Mars...
>
> Yes, yes, but wasn't there something in here a month or so agao
about
> the solar wind doing nasty things to the atmosphere if you don't
have
> a magnetic field? And if we assume that one is needed (for whatever
> reason), how do we go about putting it there?
> [snikt]
>
> I remember that I heard somewhere that solar wind can "erode" an
atmosphere.
> However, I much doubt that this process is quick - my gut feeling is
that it
> would take millions of years for an atmosphere to be completely
blown away
> by the solar wind. And, since geological timescales are meaningless
for
> human civilizations, that would not be an unavoidable obstacle for a
Mars
> terraformation project - people would be content in living in a
planet for
> mere tens of thousands of years, which by the way is many times the
whole
> human history so far.
>
> But okay, lets assume that, for some obscure reason, people could
not live
> in a planet without a magnetic field and the terraformers would have
to
> build one from scratch. Well, I am kind of short in wacky ideas
right now,
> but anyway it seems to me that a way to do that would be to build a
gigantic
> superconducting ring in orbit around the planet (perhaps Phobos and
Deimos
> could be consumed to do that, perhaps they would need a whole bunch
of
> asteroids, I don't know). This Ring of Power (sorry, I could not
avoid a
> reference to Tolkien ;-) could be powered by hundreds of solar power
> stations connected to it, and then it would soon be teeming with a
really,
> really huge electric current. As a consequence, it would generate a
magnetic
> field of planetary scale. Since the ring would be superconducting,
the
> energy losses would be extremely small (compared to the total energy
stored
> in the Ring) and mainly due to deceleration of charged particles, I
think;
> the SPSs could easily replenish those losses. And, as a result of
this weird
> planetary magnetic field architecture, I doubt that there would be
auroras
> over the Martian poles; instead, perhaps there would be a toroidal
aurora