Human Mars Mission Impossible?

"Ool" wrote in message ...
"Alex Terrell" wrote in message om...

It seems producing oxygen from Al2O3, whilst liberating aluminium, is
harder.

From what I know even on Earth it can only produced by processes in
excess of 1,000°C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000°C on a sunny day--and all days on the
Moon are sunny.

The only problem would be finding material to contain such a hot envi-
ronment. What is used on Earth for that? Some ceramic material no
doubt... If it could not be produced on the Moon I suppose it would
have to be imported from Earth. Hopefully the supply of oxygen will
create a demand, thus making smelting equipment from Earth afforda-
ble...

Actually rutile--the byproduct you get from extracting oxygen out of
ilmenite--seems to have a melting point of over 1,800°C. (They also
suggest this for Lunar heat-shield material for a return trip to
Earth...)


--
__ “A good leader knows when it’s best to ignore the __
('__` screams for help and focus on the bigger picture.� '__`)
//6(6; ©OOL mmiv :^)^\\
`\_-/ http://home.t-online.de/home/ulrich....lmann/redbaron \-_/'

"Ool" wrote in message
...


From what I know even on Earth it can only produced by processes in
excess of 1,000°C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000°C on a sunny day--and all days on the
Moon are sunny.

And all the nights are long and dark.

The only problem would be finding material to contain such a hot envi-
ronment. What is used on Earth for that? Some ceramic material no
doubt... If it could not be produced on the Moon I suppose it would
have to be imported from Earth. Hopefully the supply of oxygen will
create a demand, thus making smelting equipment from Earth afforda-
ble...

Breaking up the highland feldspars would also produce plenty of sili-
con for solar panels--and possibly glass production would become fea-
sible...



--
__ "A good leader knows when it's best to ignore the __
('__` screams for help and focus on the bigger picture." '__`)
file://6(6; ©OOL mmiv
:^)^\\
`\_-/ http://home.t-online.de/home/ulrich....lmann/redbaron \-_/'

"Chosp" writes:

"Ool" wrote in message
...


From what I know even on Earth it can only produced by processes in
excess of 1,000°C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000°C on a sunny day--and all days on the
Moon are sunny.

And all the nights are long and dark.

Yep, that's why you set up the solar power plants at the poles, or you
put three or more plants around the Moon and run "intercontinental"
cables. An alternative would be to have satelites to reflect
microwaves or laser energy from ground station to ground station.


--
__Pascal_Bourguignon__ http://www.informatimago.com/
There is no worse tyranny than to force a man to pay for what he doesn't
want merely because you think it would be good for him.--Robert Heinlein
http://www.theadvocates.org/

"Chosp" wrote in message news:KHDTb.39037$F15.392@fed1read06...
"Ool" wrote in message
...

From what I know even on Earth it can only produced by processes in
excess of 1,000C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000C on a sunny day--and all days on the
Moon are sunny.

And all the nights are long and dark.


They are?

Well, then let's make aluminum during the day!



--
__ “A good leader knows when it’s best to ignore the __
('__` screams for help and focus on the bigger picture.� '__`)
//6(6; ©OOL mmiv :^)^\\
`\_-/ http://home.t-online.de/home/ulrich....lmann/redbaron \-_/'

Ool wrote:
"Alex Terrell" wrote in message om...
"Ool" wrote in message ...

Yes, I know it's actually rather hard to free the oxygen from the lu-
nar soil, and that the only reason why it makes sense is because it
would be cheaper than oxygen from Earth's gravity well. Nevertheless,
"oxygen" *is* the magic word to rally support both from the scientific
community as well as the general public.

Agreed?

No. Producing Oxygen and Iron is not too difficult. Just add hydrogen
and electrolyse the water. Lunar rogolith might even release enough
hydrogen to make up any leakages.

It seems producing oxygen from Al2O3, whilst liberating aluminium, is
harder.

From what I know even on Earth it can only produced by processes in
excess of 1,000?C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000?C on a sunny day--and all days on the
Moon are sunny.

The only problem would be finding material to contain such a hot envi-
ronment. What is used on Earth for that? Some ceramic material no
doubt... If it could not be produced on the Moon I suppose it would
have to be imported from Earth. Hopefully the supply of oxygen will
create a demand, thus making smelting equipment from Earth afforda-
ble...

Remember that coolingi stuff is infinitely easier on Earth. Also, considering
the weight of such a beast it will have to work for a very long time until
you reach the point where it has paid back the cost of moving it from Earth
to Moon. If you don't achieve that, you are better off lifting things from
Earth.

Remember - the per kg cost of lunar materials will be directly linked to the
cost of launching the machinery from Earth. So if say at some point due to
greatly reduced launch costs getting things to moon costs the same as presently
just launching to LEO - that is say $10000/kg, then to have raw iron cost of
$1/kg (which is not exactly low) it will have to produce 10000 times its weight
in iron. And of course - unmachined iron is not exactly useful which means
lifting even more heavy machines to moon.


Breaking up the highland feldspars would also produce plenty of sili-
con for solar panels--and possibly glass production would become fea-
sible...


Silicon is only *one* of the things you need, and having raw chunks of
silicon doesn't give you a solar battery. And the process takes lots of
energy (which comes from where? lifting lots of solar patteries from earth?)
and has a long payback time.

--
Sander

+++ Out of cheese error +++

Ool wrote:
"Alex Terrell" wrote in message om...
"Ool" wrote in message ...

Yes, I know it's actually rather hard to free the oxygen from the lu-
nar soil, and that the only reason why it makes sense is because it
would be cheaper than oxygen from Earth's gravity well. Nevertheless,
"oxygen" *is* the magic word to rally support both from the scientific
community as well as the general public.

Agreed?

No. Producing Oxygen and Iron is not too difficult. Just add hydrogen
and electrolyse the water. Lunar rogolith might even release enough
hydrogen to make up any leakages.

It seems producing oxygen from Al2O3, whilst liberating aluminium, is
harder.

From what I know even on Earth it can only produced by processes in
excess of 1,000?C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000?C on a sunny day--and all days on the
Moon are sunny.

The only problem would be finding material to contain such a hot envi-
ronment. What is used on Earth for that? Some ceramic material no
doubt... If it could not be produced on the Moon I suppose it would
have to be imported from Earth. Hopefully the supply of oxygen will
create a demand, thus making smelting equipment from Earth afforda-
ble...

Remember that coolingi stuff is infinitely easier on Earth. Also, considering
the weight of such a beast it will have to work for a very long time until
you reach the point where it has paid back the cost of moving it from Earth
to Moon. If you don't achieve that, you are better off lifting things from
Earth.

Remember - the per kg cost of lunar materials will be directly linked to the
cost of launching the machinery from Earth. So if say at some point due to
greatly reduced launch costs getting things to moon costs the same as presently
just launching to LEO - that is say $10000/kg, then to have raw iron cost of
$1/kg (which is not exactly low) it will have to produce 10000 times its weight
in iron. And of course - unmachined iron is not exactly useful which means
lifting even more heavy machines to moon.


Breaking up the highland feldspars would also produce plenty of sili-
con for solar panels--and possibly glass production would become fea-
sible...


Silicon is only *one* of the things you need, and having raw chunks of
silicon doesn't give you a solar battery. And the process takes lots of
energy (which comes from where? lifting lots of solar patteries from earth?)
and has a long payback time.

--
Sander

+++ Out of cheese error +++

Ool wrote:

Actually rutile--the byproduct you get from extracting oxygen out of
ilmenite--seems to have a melting point of over 1,800?C. (They also
suggest this for Lunar heat-shield material for a return trip to
Earth...)


But it doesn't like the idea of sticking together in a suitable shape,
at least not without a lot of coaxingand energy yet.

Besides - you will need to import that oxygen-liberating equipment first.

--
Sander

+++ Out of cheese error +++

Ool wrote:

Actually rutile--the byproduct you get from extracting oxygen out of
ilmenite--seems to have a melting point of over 1,800?C. (They also
suggest this for Lunar heat-shield material for a return trip to
Earth...)


But it doesn't like the idea of sticking together in a suitable shape,
at least not without a lot of coaxingand energy yet.

Besides - you will need to import that oxygen-liberating equipment first.

--
Sander

+++ Out of cheese error +++

Pascal Bourguignon wrote in message .. .
"Chosp" writes:

"Ool" wrote in message
...


From what I know even on Earth it can only produced by processes in
excess of 1,000°C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000°C on a sunny day--and all days on the
Moon are sunny.

And all the nights are long and dark.

Yep, that's why you set up the solar power plants at the poles, or you
put three or more plants around the Moon and run "intercontinental"
cables. An alternative would be to have satelites to reflect
microwaves or laser energy from ground station to ground station.

Chosp makes a good point, probably unintentionally. Certainly blast
furnaces on Earth are kept going 24 hours per day to reduce thermal
stresses. Perhaps the structure could be wrapped in a mirror at night
to keep it hot. I guess a miniumum temperature is the 1500 melting
point of iron. For the moon though, we could afford to use more
expensive materials if they last.

I don't think energy intensive processes at the poles would really
work too well. It would need to be placed vertically and rotate, which
rather limits its size and adds cost.

Satellite Solar Power at L1 is the best option, but not in the
immediate term. This would use microwaves for large scale power
transmission and laser for vehicle propulsion, probably using a heat
engine rather than solar cells to receive the power.

Pascal Bourguignon wrote in message .. .
"Chosp" writes:

"Ool" wrote in message
...


From what I know even on Earth it can only produced by processes in
excess of 1,000°C. I'm confident those can be achieved by simply fo-
cussing enough sunlight in one spot. I know of solar ovens on Earth
that can produce up to 2,000°C on a sunny day--and all days on the
Moon are sunny.

And all the nights are long and dark.

Yep, that's why you set up the solar power plants at the poles, or you
put three or more plants around the Moon and run "intercontinental"
cables. An alternative would be to have satelites to reflect
microwaves or laser energy from ground station to ground station.

Chosp makes a good point, probably unintentionally. Certainly blast
furnaces on Earth are kept going 24 hours per day to reduce thermal
stresses. Perhaps the structure could be wrapped in a mirror at night
to keep it hot. I guess a miniumum temperature is the 1500 melting
point of iron. For the moon though, we could afford to use more
expensive materials if they last.

I don't think energy intensive processes at the poles would really
work too well. It would need to be placed vertically and rotate, which
rather limits its size and adds cost.

Satellite Solar Power at L1 is the best option, but not in the
immediate term. This would use microwaves for large scale power
transmission and laser for vehicle propulsion, probably using a heat
engine rather than solar cells to receive the power.