A reason to go to Mars

Well if we compare what it takes to set up a Mars base of
fewer than a hundred people to what it takes to build
Island One, with its ten thousand inhabitants, then yeah,
the Mars base is a lot easier and cheaper.(*)

But of course, you wouldn't START with Island One, any
more than you would START with Lowell City. What you
would do is gradually build larger and larger facilities
(such as hotels) until it became more economical (and
politically acceptable) to just go ahead and build Island
One at last. And really, you can house quite a few people
in orbit for not that much mass.

>From _The High Frontier_, pg. 324:
"A colony providing half of Earth's gravity(*) at the
equator and rotating three times per minute would be 100
meters in diameter, would have the right land area for
five hundred people, and would require a pressure-shell
mass of only 700 tons. The smallest scale colony of the
spacious, visually open spherical design would be 60
meters in diameter, would house 150 people comfortably,
and would require only 130 tons in its spherical pressure
shell."

Dr. O'Neill goes on to say that the material for the
smaller hab could come from just four Space Shuttle
external fuel tanks. I note also that less than a dozen
Saturn V launches could also do the job.

Oh, and why do the Lunar power plants have to be nuclear?

(*) One might argue that half won't be enough, if one third
is enough (and Mars advocates say it is), then half will be
enough. In any case, if you think it won't be, then double
the masses.

The wonderful thing about tethers,
Is tethers are wonderful things.