melted lunar crater basin telescope 1

[cdnprodigy]

I've an idea that many people tell me has already been discussed elsewhere, but I haven't been able to google any references to it.

The concept is to shine a mirror onto a lunar rover that is carrying a Fresnel Lens, or to utilize an Arecibo type of apparatus; this is to heat and melt portions of the surface of a Lunar impact crater basin so that it may be utilized as the dish for an infrared or radio telescope. Not to form the foundation of a dish, but to actually form the substrate of it. No mirror materials would need to be transported from earth.
I've read a paper stating Lunar impact basins form a parabolic geometry, but I don't know if this means irregular rough parabolic, or telescope quality parabolic. I would think there are enough impact sites that to find a few suitable sites, ideally near polar regions for long exposures. I don't know if melted regolith (or whatever a crater basin interior surface is called) reflects EM wavelengths enough to act as mirrors. I think some crater basins have a large metallic component, but I don't know if this is large enough to be useful for some EM wavelengths.

Any thoughts anyone has on this would be most appreciated. There are many fields at play here and I've been told this isn't feasible. No one has said specifically why...

 

[IRstuff]

Not sure what your paper says, but the Arizona meteor crater is hardly parabolic.

And what's the purpose? VLBI for radio astronomy already works on the scale of hundreds of miles.

IR telescopes require fairly precise surface figures to make decent images. And a telescope that constantly has the Earth in the field of regard is sort of pointless, since the light pollution from the Earth is probably enough to screw up the imagery.

TTFN

 

[cdnprodigy]

http://www.lpl.arizona.edu/~jmelosh/impact_crater_collapse.pdf

This is the only paper I could find referencing the geometry of lunar impact craters. They are formed very differently than are earth impact craters. A polar lunar crater would always be pointed straight up or straight down; earth would not be in the field of view, the crater's rim should shield against earth-based EM interference (maybe not for radio wavelengths).

 

[btrueblood]

Ah, but IRstuff, on the dark side of the moon, the field of view would always be away from the earth. It would, however, have the sun in view for several days out of a month...

 

[cdnprodigy]

More digging around has revealed bad news. I think the only EM wavelengths that could handle geometries as imprecise as a crater basin would be long radiowaves. These need a metal antannae dish (right?). A small iron meteorite impacting would form a nice breccia "dish", but the debris from the impact event settles down afterwards and covers the "metallic breccia". I would think it probably buries the useful metallic part too deeply. It would have had to been as lunar-equatorial as possible to avoid earth based and auroral interference.

I want to accelerate Lunar mining as quickly as possible. I thought there was something here for a minute....

 

[grvaughan]

Probably the best way to "accelerate Lunar mining" would be to simply bring back regolith and loose rocks and sell them on eBay.

As far as Lunar astronomy goes, among the main advantages of radio astronomy from the Moon are the low-noise environment found on the far side and the stable surface for VLBI:

http://www.spaceagepub.com/ilo/ilo.testimonials.html

If anyone is interested in learning more about this, the following page has a lot of links for papers on both radio and optical astronomy from the Moon:

http://www.astro.gla.ac.uk/users/yuki/reference.html

VLBI is a promising technology that could yield a valuable early Lunar application mission, i.e. rovers that set out a network of receivers at various points on the surface. My recollection is someone did a paper on that about 20 years ago, but I don't know if anything more has been done.

We need to start coming up with some fairly simple but innovative missions that can be flown to the Moon that actually start to do some of the things only talked about for so long, such as astronomy, a Lunar oxygen pilot plant, and who knows what else if we put some creativity into it.

Check out my aerospace site, AeroGo [

http://www.xanga.com/AeroGo

]

I also comment on technology in general, business, etc., on my blog
All Things [

http://allthings.blogsome.com/

]

 

[kenvlach]

cdnprodigy,
The surface of the moon is covered with metal oxides in approximately the same proportion as the Earth's crust. Possibly you could apply enough heat to a crater to produce an obsidian-like reflector. A nuclear device might produce both a large crater & a glassy surface. However, how on Earth (figure of speech) would you aim the thing???
Perhaps, a collector to generate electricity or heat.

There were lots of analyses & proposals for lunar mining based upon the samples brought back by Apollo 11 in 1969. Too early for the original work to be on the Internet, but I'm sure you can find lunar mining proposals via Google. The basic idea uses solar furnaces (mirrors to collect sunlight, plus mirrors etc. to reflect back radiated heat from heated samples). The objective is to smelt the ores into molten metal + oxygen. In some versions, hydrogen brought from the Earth aids the metal oxide reduction & produces water. If you can supply funding, I can provide the thermochemistry.

The Mars exploration proponents have similar ideas; additionally some utilize dissociation of the CO[sub]2[/sub] atmosphere.

I noticed two Apollo 11 rocks books on eBay, e.g., Proceedings of the Apollo 11 Lunar Science Conference - Volume II: CHEMICAL AND ISOTOPE ANALYSIS 945 pages (1970),

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=6598784819&rd=1&sspagename=STRK:MEWA:IT&rd=1

 

[grvaughan]

Perhaps the definitive book on Lunar rocks from the Apollo and Luna data is the Lunar Sourcebook, if you can find it:

http://www.amazon.com/gp/product/05...102-6721553-9695309?s=books&v=glance&n=283155

I jumped and bought the first edition back in 1991, and then cringed when I read there was a second edition coming, but apparently it never got published. This volume is lacking the results from Clementine, Lunar Prospector, etc. and so is already out of date, but has a lot of info. It is very dry reading!

Does anyone know of a good summary of data from the more recent missions?

What's needed even more is a good summary of what we still don't know, which is probably a lot more than people think. Obviously we don't have any hard data (e.g. cores) for stuff more than a meter down, nor hardly any good info on strata, since missions didn't really get into craters, etc.

Check out my aerospace site, AeroGo [

http://www.xanga.com/AeroGo

]

I also comment on technology in general, business, etc., on my blog
All Things [

http://allthings.blogsome.com/

]

 

[grvaughan]

Maybe we're not the only ones thinking about astronomy from the Moon just now - Lunar Enterprise Daily [

http://www.spaceagepub.com/

] just reported today that both NASA and the Italians are looking into it

http://www.spacedaily.com/reports/Griffin_Vows_To_Send_Shuttle_Mission_To_Hubble.html

[at end]

The Italians are setting aside 150 million Euros for a project to use robots to build some sort of telescope or array in a (non-melted) Lunar crater

http://www.ansamed.it/ansamed/news/nations/italy/20060104143333779197.html

That sounds like a lot for 150 Million Euros, but maybe they'll get ESA to chip in some more. Actually, the big story here may be that Italy is getting more interested in the Moon.

Each ESA country tends to have certain particular interests, and if one of them will start pushing more for Lunar exploration/utilization, that would be a big step forward.

Check out my aerospace site, AeroGo [

http://www.xanga.com/AeroGo

]

I also comment on technology in general, business, etc., on my blog
All Things [

http://allthings.blogsome.com/

]

 

[cdnprodigy]

The "bring back rocks" economy works for a while. The Apollo missions brought back a few hundred kg and a single mission could easily double this. I think you could easily fetch $1/mg. But for larger payloads, I'm thinking the market would start to bottom out, and you would need to bring back more than just regolith/rocks.

I think the total price of that Italian telescope array is in the billions.

The nuked crater is a fascinating idea, surely the cheapest solution. But detonating a nuke for commercial purposes would probably not be politically palatable, especially just for a telescope. Also, would debris from the nuke detonation settle afterwards upon the newly created glassy surface in a similiar fashion as settling debris ruins the original meteor impact Lunar surface (breccia)? Would Lunar debris from the detonation extend to earth GEO/LEO satellite orbits?

 

[kenvlach]

cdnprodigy,
Please study up on lunar mining; it has essentially nothing to do with the "bring back rocks" idea.

Lunar mining would produce structural alloy materials for a moon station, orbiting space stations & interplanetary travel. Much easier to boost things into space from the Mooon, with 1/6th of the gravity, than from Earth. Metals are more easily prepared by smelting in the absence of air & oxygen. Like having a vacuum furnace.
The dissociation of metal oxide ores would also produce oxygen for breathing and for fuel. Only necessary to transport lightweight hydrogen there (if no frozen water can be found at the polar regions).

Nuking out a crater is mostly an academic exercise; it would never get approved. I doubt much debris would fall back on the crater surface. It would exit at high velocity, there's no constraining atmosphere & gravity is very low.

Cheers.

 

[WKTaylor]

cdnprodigy...

Lunar and Mars optical observatories will have a major problem with an environmental element: dust. See following articles for a glimpse of the problem on the moon [dogpile.com search "lunar dust hazard"].

http://www.lpi.usra.edu/meetings/leag2005/pdf/2043.pdf

http://www.space.com/scienceastronomy/051207_moon_storms.html

http://www.nasa.gov/centers/marshall/multimedia/photos/2005/photos05-144.html

http://www.signonsandiego.com/uniontrib/20050427/news_lz1c27moon.html

http://www.wired.com/news/space/0,2697,67110,00.html

The challenges on Mars are equally formidable... see MER website

http://marsrovers.jpl.nasa.gov/home/index.html.

Dust accumulation due to vehicle movement [soil disturbance] and dust-storms [including dust-devils] is massive.

Regards, Wil Taylor

 

[cdnprodigy]

http://www.space.com/adastra/adastra_moondust_060223.html

Looks like NASA is taking this up, so my work is done. They wanna utilize magnetrons (microwaves) to solidify the regolith. I was hoping this would be a cheap low maintenance observatory. Sweeping the dish is expensive. The photoelectric effect on the Moon kills this idea, I think. Thx Wil. Kenvlach, I've read extensively about mining the Moon and it is absurdly expensive until robotics technology advances significantly. We would also need either processed rocket fuel (O2 or H2) from the Lunar poles or a Lunar Space Elevator in operation. I'm looking for currently engineerable Lunar utilities. I agree though, harvesting precious metals is the way to sustainably open up a Lunar Economy.