

Moon Not Only Has Water, but Lots of It - charlief
http://online.wsj.com/article/SB10001424052702303339504575566194097878552.html?mod=e2tw

======
j_baker
"about twice the quantity seen in the Sahara Desert"

Ok, surely there _has_ to be something better to compare this to than one of
the largest deserts in the world.

~~~
ceejayoz
I think the point they're trying to make is that people are able to live on
the amount of water in the Sahara, so lunar colonisation is therefore feasible
from the water front.

------
erikstarck
I wonder what it would take for some nation or über-nation to set the goal to
terraform Mars. That would be a goal worthy of mankind in the 21st century.

~~~
hugh3
As a first step it might be more useful to terraform, say, Mexico. Or
Australia.

~~~
charlief
Maybe some of the ecological aspects, but changing the atmosphere and climate
sounds like a risky affair. I'm pretty sure if we were able to do some heavy
handed climate modification, we would want to do it somewhere else, not in a
fragile environment like Earth where extinction or at least long-term
catastrophe of many ecosystems is on the table.

------
Groxx
> _He and his colleagues estimate that 5.6% of the total mass of the targeted
> lunar crater's soil consists of water ice. In other words, 2,200 pounds of
> moon dirt would yield a dozen gallons of water._

5.6%: impressively high, wouldn't have guessed that at all. Though it _was_ in
a crater, so could be abnormal.

2,200 pounds of moon dirt: weighed _here_ or _there_? Where's metric when you
_need_ it, instead of where it's a PITA (mass instead of volume in cooking ==
?!) ?

edit: that's one of the lamest animations I've seen in a while... where did
they get it? Remind me to black-list the animator(s).

~~~
zokier
2200 pounds on moon is same as 2200 pounds here.

~~~
ComputerGuru
No it's not. 2200 pounds on earth is 363 pounds on the moon (moon's gravity is
0.165 that of earth's).

1000 kilograms on the moon is 1000 kilograms on earth and vice versa. Pounds
is a measure of _weight_ and not _mass_. Weight depends on the strength of the
gravitational pull.

Also, please note that when people in Europe say they weight "75 kilograms,"
they're lying. What they mean is, they weight 75 kilograms-force or kilogram-
pounds, which are again measures of weight and not mass. In truth, they would
weight 7.65KG which equals 75KGF)

------
kqr2
_In other words, 2,200 pounds of moon dirt would yield a dozen gallons of
water._

What would be the best water extraction technique?

~~~
hugh3
Heat it to room temperature, squeeze it to a pressure of 1 atmosphere, and the
ice should just melt and run out the bottom.

Or just heat it until the water sublimates, then collect the vapour and cool
back down to liquid/solid.

I guess it depends on your constraints vis a vis time, energy and amount of
equipment you want to bring to the moon. It doesn't sound too tricky, but the
main part is that you have to bring the dirt "indoors".

------
hugh3
"Lots of it" seems like a bit of an exaggeration. This particular site, a
large crater close to the South Pole which manages to avoid direct sunlight,
has 5.6% water by mass, but what does that come down to in Earth terms? A
small lake? I suppose it depends how deep the water goes.

~~~
InclinedPlane
Things you can do with a small lake on the Moon:

* Create Oxygen and potable water for life support system, saving having to ship that from Earth.

* Build greenhouses with artificial lighting to grow in situ foods, saving having to ship that from Earth and vastly increasing the self-reliance of a Moon base.

* Create a rocket propellant factory (LH2 and LOX are a quite useful and indeed common propellant for exo-atmospheric spaceflight).

This means that after you set up the initial moon base and infrastructure
later missions can skip sending as much water, Oxygen, and food. And, much
more importantly, don't have to send a fully fueled return vehicle. Given the
exponential nature of the rocket equation, this is _huge_.

~~~
hugh3
Entirely true, and it's great news. But we have to be careful -- there's a
pretty limited supply of this stuff, and we don't want to waste it.

------
SudarshanP
Lots of awesome ISRU(Insitu Resource Utilization Presentations)
<http://www.isruinfo.com/index.php?page=srr_11_ptmss>

------
bitwize
Free Luna!

~~~
bsk
Right after Iran :D

------
niels_olson
Are we really discussing science from the WSJ? Any science reporting in the
WSJ is meant for the sole purpose of bolstering the non-political credentials
of what is becoming an ever more right-leaning publication, thereby allowing
its readers to participate in their own radicalization by pointing to articles
like this as evidence that their source is "fair and balanced". Politics or
pure Wall Street grist from WSJ, sure. Science?! We have plenty of better
resources for it.

