On Thu, 21 May 2009 03:42:56 +0000, Alan Erskine wrote:

"Marvin the Martian" wrote in message
news
What you really want to do is... (wait for it) ... build a
manufacturing plant on Mars. Once on Mars, you can use Martian
materials, so you don't have to bring as much mass up.

Or the Moon - nearer to Earth; no atmosphere at all (compared to Mars)
and half the gravity of Mars. Also the Moon's closer to the Sun, so
solar energy can be used for smelting materials and industrial
processes.

Smelting is a process that usually involves Carbon, which the moon does
not have. You will not be doing any smelting on the moon. The launch
costs per kg to LEO alone makes the cost per kg of any material trivial
except for precious metals. Why haul carbon to smelt on the moon, when
you can bring up the same amount of finished product? You wouldn't.

The moon also has great extremes in temperature between day and night,
and the nights are 2 weeks long. Manned missions to the moon were chosen
for the small windows when their moon suits could tolerate the
temperature. It would prove difficult to work in the light of a full
lunar day.

Yes. You get 2X the solar energy on the moon than you do on Mars.