Comments on: Mining the Moon, Fueling the Future

By: billgamesh

billgamesh — Thu, 23 Jan 2014 00:30:49 +0000

Thanks Bob! So exciting!
Yes I have always (for the last couple years anyway) advocated a human mission to Ceres instead of Mars. My logic being that because of the heavy nuclei shielding and artificial gravity requirements only nuclear energy can get us BELO (Beyond Earth and Lunar Orbit); if a real spaceship is required then Mars becomes far less attractive as being “just close enough.” Ceres becomes by far the best first HSF deep space mission.

But the downside is that it diverts public attention from the Moon, which is bad news. We cannot get to Ceres without a base on the Moon from which to launch a nuclear mission.
The Moon is the only place to get the thousand plus tons of water for space radiation shielding and the only appropriate place to assemble, test, and launch a nuclear mission.
The U.S. Navy should be interested in this as they have experience with many of the elements of a Ceres mission or other icy body; nuclear power plants, ice diving, submersibles, etc.

By: Robert Clark

Robert Clark — Wed, 22 Jan 2014 21:28:56 +0000

Undoubtedly Billgamesh will be glad to read this:

Is there life on Ceres? Dwarf planet spews water vapor into space.
Alan Boyle, Science Editor NBC News.
[i]
Infrared readings from a space telescope confirm that water vapor is rising from the surface of Ceres, and that discovery is likely to heat up interest in a strange world that’s the biggest asteroid as well as the smallest known dwarf planet.
The find comes just in time. Next year, NASA’s Dawn spacecraft is due to go into orbit around Ceres and is likely to address some of the questions raised in Thursday’s issue of the journal Nature: Where is the water vapor coming from? How is it getting into space? And what are the implications for Ceres’ place in the solar system?
“This is what you might call the ‘smoking gun,'” Mark Sykes, CEO and director of the Arizona-based Planetary Science Institute, told NBC News. “The implications could be huge for the future of astrobiology and planetary exploration.”[/i]
http://www.nbcnews.com/science/there-life-ceres-dwarf-planet-spews-water-vapor-space-2D11970722

Bob Clark

By: billgamesh

billgamesh — Fri, 17 Jan 2014 21:52:11 +0000

I am re-reading The High Frontier (1976)
Still amazing 37 years later. This book is really about using the Moon to build space colonies and financing the whole operation with solar energy satellites. “A typical Apollo sample contains, by weight, more than 20 percent silicon, more than 12 percent aluminum, 4 percent iron, and 3 percent magnesium. Many of the Apollo samples contained more than 6 percent titanium by weight-” (page 58 of the illustrated paperback version).

Still the best path for humanity.

By: Paul Spudis

Paul Spudis — Thu, 16 Jan 2014 18:16:01 +0000

You don’t need ilmenite to manufacture solar arrays — we can make amorphous silicon cells bringing the doping materials from Earth. Low efficiency, but who cares since we can make thousands of them.

Ilmenite is typically only a couple weight percent in mare soils and is virtually absent in highland soils. Only a few locales around the Moon have the high concentrations of ilmenite mentioned in that book.

By: vidbeldavs

vidbeldavs — Thu, 16 Jan 2014 15:16:37 +0000

The proposal in the The Moon: Resources and Future Development was to use the plentiful ilmenite (20% of the regolith in many regions – according to the book) to produce semiconductors and photovoltaics rather than for its oxygen or iron value. If PV cells can be produced from lunar regolith that could make large-scale space-based solar power feasible providing additional reasons to industrially develop the Moon.

By: Paul Spudis

Paul Spudis — Thu, 16 Jan 2014 13:33:14 +0000

Depends on what you are working with, but bench-scale ISRU demonstrations could be flown to the Moon on small lander spacecraft (few hundred kg payloads).

Lunar iron is always Fe2+. I do not see any immediate value in mining and returning lunar ilmenite for any commercial purpose. Ultimately, it may be useful on the Moon to support local industry, but that would be in the distant future. Water alone is value enough to jump start lunar mining.

By: vidbeldavs

vidbeldavs — Thu, 16 Jan 2014 10:38:27 +0000

How much would be needed for testing various schemes for recovery of resources from lunar regolith? The book The Moon: Resources and Future Development had a chapter on lunar ilmenite, which has a significantly wider band-gap 2.54 eV compared to 1.12 eV for silica making for the possibility of more efficient solar collectors and I believe a claim was made for higher radiation resistance. The book claims that 20% of regolith is ilmenite but that lunar ilmenite differs from terrestrial ilmenite “Lunar ilmenite is formed under reducing conditions, and consequently its iron is in the 2+ valence state. On Earth, the iron in ilmenite is only partially in the 2+ state, because there was more oxygen available during its formation. The iron in the 2+ state is responsible for the good semiconducting qualities of ilmenite, thus lunar ilmenite would be preferred for semiconductors. In the 2+ valence state, the atom has lost two of its (negatively charged) valence electrons, and thus has a net positive charge of 2.” So processing methods for lunar ilmenite cannot be readily be tested unless we secure enough from the Moon. Other materials may be similar. The initial quantities will have value beyond novelty until process testing facilities can be developed on the Moon.

By: Paul Spudis

Paul Spudis — Thu, 16 Jan 2014 09:55:27 +0000

After the first ton is brought back and the novelty has worn off, the value of future shipments declines dramatically. The principal value of bulk regolith and aggregate is for building structures on the Moon.

By: gbaikie

gbaikie — Wed, 15 Jan 2014 16:48:56 +0000

“While no one would suggest exporting simple, low-processing materials such as bulk soil (regolith) and aggregate (concrete and adobe) back to Earth, they have uses and thus enormous value on the Moon and in space for local building and other engineering requirements.”

I think it would good to have cheap lunar regolith on Earth.
Currently there is no lunar regolith to buy on Earth and I think there could be wide range of prices
for different types of lunar regolith, just as we have wide variation for diamonds.

I think short term goal of having as much lunar regolith available on Earth as gem diamonds would be very good, and then getting to point of having as much as all types diamonds, including industrial diamonds would be better than lower amount available.

So bring back to Earth, 1 ton of lunar regolith, to be sold to anyone want them to keep for various reasons, would be a very important event in history. Far more important than bringing back 1 ton of He-3.
Now to do all the mining and processing required to bring back 1 ton He-3 would be quite impressive, but having 1 ton he-3 on Earth would be of little importance. Or few people would have much interest in having this lunar He-3.
If did have such interest they don’t need the lunar He-3, Earth He-3 is available and there is no advantage of having lunar He-3 compared to Earth He-3.

So I think the day, 1 ton of lunar regolith is brought back to Earth would be important and day regular shipment of 1 ton of regolith would also be important.

And it seems there room for vast improvement in terms of bring back 1 ton of regolith- from different locations, and and kinds lunar soil and rock which brought back.

It seems that if there was wide selection of lunar samples this would quite important to lunar science, but it not just limited to a benefit to professional lunar scientists.
So I think if lunar material were in range less than price silver per gram to price of highest quality gem diamonds or rubies that this day would be one milestones of opening the space frontier.
Whereas He-3 might a be folly in such a history.

By: DougSpace

DougSpace — Wed, 15 Jan 2014 05:19:00 +0000

Thanks for posting that video. It was difficult to hear but still quite interesting.