Massive quantities of ice crystals on Mars

[Elias Sinderson]

Hey now,

	I firmly believe that human colonization of mars is 'in the cards' so to 
speak - it's not a question of if, but when. The discovery of vast 
quantities of water on Mars makes this reality much closer than 
previously imagined. Jim brought up three technologies that he feels are 
important to develop to reach this goal, and I wanted to comment on them 
(sorry for the length, good bits!):

Jim Whitehead wrote:

> Longer term, it implies that colonies on Mars are feasible. Many
> technologies need to be developed before this can happen:
> 
> * low cost launch facilities (reduce cost/kilogram of getting to earth
> orbit)


$10M/ton is close to current costs for shuttle payloads ($10K/kg).
Single-stage chemical rocket payloads can be lifted for about $4K/kg.
We may find ways to reduce this to $500/kg or even less - In particular, 
fuel (and thus mass) could be greatly reduced if we can beam microwave 
or laser energy to an ascending rocket. That could reduce energy costs 
to just a few dollars per kg. Nuclear propulsion could be similar, but 
of course there are non-economic considerations...

Another proposal to reduce the cost of lifting mass into space is that 
of a 'space elevator,' a concept first proposed (rather fancifully) in 
1895 by Konstantin Tsiolkovsky [1]. Arthur C. Clarke also wrote of such 
a technology in his 1978 novel, Fountains of Paradise. The general idea 
is that the elevator would extend from the equator in a geosynchronous 
orbit with it's center of gravity about 35,786 K (!) above the Earth. 
This idea is becoming more of a reality as we gain more experience with 
moecular nanotechnology. Several other technologies would be required 
for this project, as outlined in [2], but the general concensus is that 
we could see the thing built within 50 years (or even sooner if 
appropriate resources were allocated)!

The amount of material required to build a space elevator is immense, 
and getting them into orbit is not very feasible. For that matter, 
building anything on the ground and putting them in space make little 
sense... It makes much more sense to set up factories in space and mine 
near Earth orbit asteroids for their mineral content... The following is 
excerpted from a book by John Lewis [3]. (Lewis is/was Co-director of 
the NASA/UArizona Space Engineering Research Center, and Commissioner of 
the Arizona Space Agency.)

"As an example of the magnitude and economic value of space
resources, we shall assay the *smallest known* M asteroid and account
for its market value.  That distinction belongs to the NEA known as
3554 Amun.  Amun is only two kilometers in diameter, the size of a
typical open-pit mine on Earth, with a mass of thirty billion
(3x10^10) tons.  Assuming a typical iron meteorite composition, the
iron and nickel in Amun have a market value of about $8,000 billion.
The cobalt content adds another $6,000 billion, and the
platinum-group metals (platinum, osmium, iridium, palladium, and so
on) add another $6,000 billion.  Not counting the value of its major
nonmetallic components (such as carbon, nitrogen, sulfur, and
phosphorus) and its minor and trace nonmetallic components (such as
germanium, gallium, arsenic, and antimony), the total market value of
Amun in Earth's metals market is $20,000 billion.  Since it is
already located in space, it represents an asset that would cost
about $10 million per ton to launch from Earth, a total of
$300,000,000 billion.  That is roughly equivalent to the gross global
product of Earth for the next thirty thousand years.  Therefore, this
one small asteroid would provide us with the potential for a space
program tens of thousands of times larger in scale than anything we
could afford without the use of space resources -- indeed, far
greater than Earth's entire economy."

Jim also mentions:
> * DNA repair (lots of radiation on the Martian surface)

The amount of radiation exposure on Mars, from what I understand, is 
solar - due to the thin atmosphere. Fortunately, one of the best 
materials for radiation shielding is water. Fortunately, there appears 
to be an abundance of water on Mars. Terraforming activities could 
create more of an atmosphere over time and reduce the amount of 
shielding needed. Either way, I don't see this as a key enabling 
technology for Mars colonization.

Jim's last technology:

> * sophisticated construction robots

Agreed, although I believe that this will happen naturally in the course 
  of pursuing the first point above. There is significant research 
focused on developing teams of robots that can fix one another when they 
break down, and operate collaboratively to achieve complex tasks. So, 
although I see this as a necessary component in colonizing mars, I 
believe strongly that the key item to address is that of establishing 
factories in space and reducing launch costs. Note that once we can 
build ships in  space the only thing to get up there is the human 
component... We would also be far less constrained in our design choices 
when building space ships.


> Still, for most FoRKs, it is likely that you will see humans visiting Mars
> in your lifetime (though they may not be American -- what an enormous coup
> it would be for the Chinese to get there first).


Again, I completely agree that humans will be on Mars within the average 
FoRKs lifetime. However, I wouldn't be so bummed if another contry got 
there first... More than anything, it would excite me that we (humans) 
did it at all.


One small step,
Elias


[1] http://science.nasa.gov/headlines/y2000/ast07sep_1.htm
[2] http://flightprojects.msfc.nasa.gov/pdf_files/elevator.pdf
[3] "Mining the Sky: Untold Riches from the Asteroids,
Comets, and Planets" by John S. Lewis, 1997