Posted on 05/06/2006 2:39:58 PM PDT by Iam1ru1-2
May 5, 2006: An early, persistent problem noted by Apollo astronauts on the Moon was dust. It got everywhere, including into their lungs. Oddly enough, that may be where future Moon explorers get their next breath of air: The moon's dusty layer of soil is nearly half oxygen.
The trick is extracting it.
Right: Apollo 17 geologist Harrison "Jack" Schmitt scoops up some oxygen-rich moon rocks and soil.
"All you have to do is vaporize the stuff," says Eric Cardiff of NASA's Goddard Space Flight Center. He leads one of several teams developing ways to provide astronauts oxygen they'll need on the Moon and Mars. (See the Vision for Space Exploration.)
Lunar soil is rich in oxides. The most common is silicon dioxide (SiO2), "like beach sand," says Cardiff. Also plentiful are oxides of calcium (CaO), iron (FeO) and magnesium (MgO). Add up all the O's: 43% of the mass of lunar soil is oxygen.
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Cardiff is working on a technique that heats lunar soils until they release oxygen. "It's a simple aspect of chemistry," he explains. "Any material crumbles into atoms if made hot enough." The technique is called vacuum pyrolysis--pyro means "fire", lysis means "to separate."
"A number of factors make pyrolysis more attractive than other techniques," Cardiff explains. "It requires no raw materials to be brought from Earth, and you don't have to prospect for a particular mineral." Simply scoop up what's on the ground and apply the heat.
In a proof of principle, Cardiff and his team used a lens to focus sunlight into a tiny vacuum chamber and heated 10 grams of simulated lunar soil to about 2,500 degrees C. Test samples included ilmenite and Minnesota Lunar Simulant, or MLS-1a. Ilmenite is an iron/titanium ore that Earth and the Moon have in common. MLS-1a is made from billion-year-old basalt found on the north shore of Lake Superior and mixed with glass particles that simulate the composition of the lunar soil. Actual lunar soil is too highly prized for such research now.
Above: A lens focuses sunlight onto a vacuum chamber filled with simulated moondust, producing oxygen and "slag." [Larger image]
In their tests, "as much as 20 percent of the simulated soil was converted to free oxygen," Cardiff estimates.
What's leftover is "slag," a low-oxygen, highly metallic, often glassy material. Cardiff is working with colleagues at NASA's Langley Research Center to figure out how to shape slag into useful products like radiation shielding, bricks, spare parts, or even pavement.
The next step: increase efficiency. "In May, we're going to run tests at lower temperatures, with harder vacuums." In a hard vacuum, he explains, oxygen can be extracted with less power. Cardiff's first test was at 1/1,000 Torr. That is 760,000 times thinner than sea level pressure on Earth (760 Torr). At 1 millionth of a Torr -- another thousand times thinner -- "the temperatures required are significantly reduced."
Right: Slag--a low-oxygen byproduct of Cardiff's device. Slag may prove useful as a raw material for bricks, pavement or radiation shielding. [Larger image]
Cardiff is not alone in this quest. A team led by Mark Berggren of Pioneer Astronautics in Lakewood, CO, is working on a system that harvests oxygen by exposing lunar soil to carbon monoxide. In one demonstration they extracted 15 kg of oxygen from 100 kg of lunar simulant--an efficiency comparable to Cardiff's pyrolysis technique: more.
D.L. Grimmett of Pratt & Whitney Rocketdyne in Canoga Park, CA, is working on magma electrolysis. He melts MLS-1 at about 1,400 deg. C, so it is like magma from a volcano, and uses an electric current to free the oxygen: more.
Finally, NASA and the Florida Space Research Institute, through NASA's Centennial Challenge, are sponsoring MoonROx, the Moon Regolith Oxygen competition. A $250,000 prize goes to the team that can extract 5 kg of breathable oxygen from JSC-1 lunar simulant in just 8 hours.
The competition closes June 1, 2008, but the challenge of living on other planets will last for generations.
Got any hot ideas?
L
O2? Watch Robertson Crusoe on Mars. The monkey with the sausage is good too.
Turn on the Terra-forming machines. By the way, which way is Mecca from the moon?
Personally, I find Mars much less attractive than the moon for colonization. The only advantage that Mars has in my opinion is near-earth-like gravity, and that is both a blessing and a curse. The gravity well is what prevents our easy access to space. Leaving the moon's gravity is much easier than leaving either the Mars' or the earth's. The moon is closer, by far, of course. Both Mars and moon residents will need pressurized habitats and breathing equipment. The total lack of an atmosphere is in some ways an advantage, as there's no dust and grit flying around to gum up equipment. Also, solar arrays would better without an atmosphere in the way.
For the record, I'm a fan of building space habitats instead of colonizing planets. The question was first posed by G. K. O'Neill, who asked whether planets are really the best choice for settlements beyond the earth. I tend to agree with his assessment, that they are not. And we should instead work towards building Babylon 5 like space stations.
I believe Praxair used to be Union Carbide's air products division. I think it was called Linde.
I wouldn't say there is zero proof. Clearly there is some proof that water exist on the moon and there is some proof that it does not. But how can you be certain either way?
http://www.space.com/scienceastronomy/060306_lunar_ice.html
Gonna quibble with that- there is no "proof" either way whether the moon has water but there is certainly some evidence pointing to it. That being said, the real question is obtaining water economically whether by importing it, producing it from native materials or capturing and redirecting the occasional passing comet.
You're right. Praxair, Air Liquide, BOC and other gas industrial giants can solve this problem.
Read the High Frontier by O'Neill. His factories have varied gravity gradients based on their distance from the rotational diameter. This is why he speculates that at the end of there mile lon cylinders you could "climb the clyinder wall and gravity would be decreasing as you"go up". He speculates that a pair of wings would allow a "spacer" to fly!!!
And then act surprised when the hot gas immediately oxidizes something else.
I think you are correct. I believe the gas side of Linde became Praxair. The welding, cutting & automation portions of Linde was spun-off as L-Tec. I worked in automated cutting.
L
I wrote an article which is posted at our web site. Check it out:
Ballet Dancers in Space
I'll thank you in advance for the link.
Regards,
L
I don't have a website but our National Space Society of North Texas has a Yahoo Group and you are linked to that site where serveral of my articles and message reside.
The monkey with the sausage is good too.
I've never tried that, is it spicy?
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