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That lunar dust is "not hazardous", read this: MICRO-MORPHOLOGY AND TOXICOLOGICAL EFFECTS OF LUNAR DUST The part about "glass shards" really brings the "point" home.

Umm, I actually read one of her papers. Check this quote out: ..."The K-T mass extinction is unique in that at least two short-term events (one impact and
one volcanic, or two impacts?) are superimposed upon the long-term late Maastrichtian climate
record. The mass extinction began at the time of maximum global cooling during the late
Maastrichtian which ended with a short-term warm event of 3-4C between 200-400 ky prior to
the K-T boundary and may have been triggered by major volcanism or a pre-KT impact event
(age of oldest of three spherule layers in new NE Mexico sections, Stinnesbeck et al., this vol.).
This warm event was followed by 2-3C cooling during the last 100 ky of the Maastrichtian (Li
and Keller, l998). Species extinctions accelerated during this final phase of cooling and reached a
maximum at the K-T boundary with the extinction of all tropical and subtropical species
coincident with an impact event (Ir anomaly)"....

From http://www.lpi.usra.edu/meetings/impact2000/pdf/30 29.pdf

The issue of global environment is, of course, somewhat heated, but could someone explain to me how, in light of this (and other paragraphs) the article cited in the original posting is anything but outright misrepresentation?

Perhaps you're thinking of the previously mentioned http://www.tass-survey.org/richmond/answers/lunar_ lander.html which includes some images from the slide show at http://www.lpi.usra.edu/publications/slidesets/apo llolanding/ApolloLanding/apollolanding_index.shtml

Here's a link

Ok, here : http://www.niac.usra.edu/files/library/meetings/fe llows/mar04/897Kare.pdf

No, I want to do this : http://www.niac.usra.edu/files/library/meetings/fe llows/mar04/897Kare.pdf

Ok, for all the nay-sayers : here's a pdf showing how laser launch works and WHERE TO BUY THE PARTS TODAY! http://www.niac.usra.edu/files/library/meetings/fe llows/mar04/897Kare.pdf You know, because we can make one of these today, not next century cuz we actually have available everything we need.

http://www.marsis.com/index.php3?page=document_men u.php3

Already we have some intriguing scans of layered terrains... http://www.lpi.usra.edu/meetings/polar2006/pdf/807 0.pdf

...and as the mission progresses more observations will allow constraints on water distibution to be made over much of Mars' globe.

There's the idea of laser launch - instead of providing the energy to vapourize propellant with chemical reactions, you aim a laser at the spacecraft to do the job.

Secondly, there's a variety of space tether schemes that don't go all the way down to the surface; instead, they dip down to an altitude and relative velocity where they could be met by hypersonic rockets. These have the rather large advantage of not requiring super-nanotubes. here is a NASA-funded study on the idea.

And, of course, there's always Project Orion - explode nuclear bombs beneath a gargantuan steel plate to push the thing along...but somehow I don't see that one getting approved any time soon :)

is one scheme: http://www.niac.usra.edu/files/library/meetings/fe llows/mar04/897Kare.pdf

Current technology, low technical risk, capital cost in the $1B - 10B range depending on system size and the cost scaling of the lasers. (The nominal number is $2 billion for a system with 3000 tons/year capacity). Marginal launch cost at least as low as the first generation of space elevators. Growth path to any desired payload size and annual launch capability, and to marginal costs well below $100/lb.

For that matter, fully-reusable rockets can have marginal costs in the same range as the Space Elevator. The capital costs and technical risk are higher than for laser launch, but probably lower than for the Space Elevator.

Space elevators may (or may not) be the cheapest route from Earth to space once transport costs are close to the raw fuel (energy) cost, but we're a very long way from that point.

We need a new superhero. He will be called The Googler and he will bring enlightenment to the world in the form of teaching people to find information for themselves. Did they stop teaching that since I was in school many moons (get it, MOONS) ago?.

PS: Here's one of the many publically available maps of mineral resources on the moon: http://www.lpi.usra.edu/resources/clemen/clemen.ht ml

Meteors are bits of dust or rock that plunge into the Earth's atmosphere and burn up, making bright streaks in the sky.

This technology was first [1993] published as "Artificial Meteorite Strike Spectroscopy" to seek water at the poles of Mercury, now NASA will do it on the Moon. This paper referenced Bruce Murray et al. hypothesizing water at the Lunar poles. HUMAN AND ROBOTIC PRECURSOR MISSIONS TO THE POLAR ICECAPS OF MERCURY Proceedings of The High Frontier Conference XI: Bringing the Vision of Space into Reality, 11th in a series formally known as the Space Manufacturing Conference, Space Studies Institute, Princeton, NJ, June 1993 [and see also the reference to this in "The Ball-bearing Bowling Alternative: Wild Strikes for Polar Ice", Mercury Messenger, Issue 6, July 1994, p.4] Jonathan V. Post, "Mars Polar Cap and Mercury Polar Cap Manned Science Missions", unscheduled talk at Mars Session, Session co-chairman Willy H. Sadeh, AIAA 30th Aerospace Sciences Meeting & Exhibit, Reno, NV, 7 January 1992 [included 1st detailed public presentation of manned Mercury polar mission proposal] Jonathan V. Post, "Lunar Farside, Mars Polar Cap, and Mercury Polar Cap Neutrino Experiments", Proceedings of Space 92 (3rd International Conference on Engineering, Construction, and Operations in Space), pp.2252-2263, ed. Willy H. Sadeh, Stein Sture, Russel J. Miller, 31 May - 4 June 1992, Denver, CO, AIAA/American Society of Civil Engineers, New York [included 1st publication of manned Mercury polar mission proposal]

I stand slightly corrected. Apollo 12 did pick up pieces of Surveyor III. I'm still waiting to be convinced about Apollo crews picking up something left by a previous crew.

WTF? are we talking about crews sneaking over to other apollo landing sites on the moon?

For those of you who are skeptical about the necessary nanotube unobtanium for the full space elevator becoming available any time soon, here's a link to a proposal that requires more feasible properties out of a tether, but still helps to lower launch costs a lot: Hypersonic Airplane Space Tether Orbital Launch (HASTOL) Study - Phase II.

This might be a troll, but oh well..

Look at it another way: Try finding a small car on Earth from the Moon using telescopes. It isn't going to happen. For reference, try looking at this picture.

And we can't see planets a "brazilian light years away", we can detect them when they pass in front of their parent star because that star will dim just a little bit.

It should be noted, however, that the Clementine satellite (orbited the Moon for a little bit) did image the Apollo 15 landing site at Hadley Rille. More about that here.

I've been trying to figure out a software engineering project fun and out there enough to get funded by these guys, but nothing springs to mind yet :)

I've been trying to figure out a software engineering project fun and out there enough to get funded by these guys, but nothing springs to mind yet :)

The positive feedback loop associated with the difference in albedo between sea ice and open water is generally recognized. Another, potentially more powerful feedback loop that is not as widely known is the potential huge release of methane from the arctic permafrost. First, note that atmospheric methane is a very strong greenhouse gas, about 8 times stronger than carbon dioxide. According to http://www.fe.doe.gov/programs/oilgas/hydrates/,

"Methane hydrate form in generally two types of geologic settings: (1) on land in permafrost regions where cold temperatures persist in shallow sediments, and (2) beneath the ocean floor at water depths greater than about 500 meters (about 1,640 feet) where high pressures dominate. The hydrate deposits themselves may be several hundred meters thick." "In 1995, the U.S. Geological Survey (USGS) completed its most detailed assessment of U.S. gas hydrate resources. The USGS study estimated the in-place gas resource within the gas hydrate of the United States ranges from 112,000 trillion cubic feet to 676,000 trillion cubic feet, with a mean value of 320,000 trillion cubic feet of gas. Subsequent refinements of the data in 1997 using information from the Ocean Drilling Program have suggested that the mean should be adjusted slightly downward, to around 200,000 trillion cubic feet -- still larger by several orders of magnitude than previously thought and dwarfing the estimated 1,400 trillion cubic feet of conventional recoverable gas resources and reserves in the United States. Worldwide, estimates of the natural gas potential of methane hydrate approach 400 million trillion cubic feet -- a staggering figure compared to the 5,500 trillion cubic feet that make up the world's currently proven gas reserves."

I was interested in what proportion of the methane hydrate reserves were located in the permafrost region, and how much methane release might result from melting of the permafrost. Here is some revealing information:http://www.lpi.usra.edu/meetings/geoma rs2001/pdf/7035.pdf

From the above link we learn that oceanic hydrate contains up to 95% of all naturally occurring hydrate worldwide. The methane deposits under the permafrost are at least 200m deep, some much deeper, and those deposits constitute an estimated 5% of total methane hydrate deposits on Earth. So the actual estimate of methane trapped beneath the permafrost is estimated at 5% of 400 million trillion cubic feet of methane is:

2,000,000,000,000,000,000 cubic foot = 56,633,693,423,376,624,568 liters, trapped below the permafrost.

Now, further: "What matters for climate change is methane mass (kg or tonne). Normally, volume (m3) or flow rate (m3/h) is measured using some measurement device or instrument, and these volume values are converted to mass (kg or kg/h). An intermediate step usually involves adjusting the measured volume by measured pressures and temperatures to volumes at standard conditions (0 C and 1 atm, equal to 1.013 bar)." http://cdm.unfccc.int/methodologies/inputsconsmeth /MGM_methane.pdf

So for methane, "1 gm mole occupies 22.4 litres at 273 K and 1 atm.

C 12.01115

H 1.00797

16.043 g CH4 = 22.414 litres

Density (16.043 / 22.414) = 0.7157 g/litre or kg/m3.

So 56,633,693,423,376,624,568 liter * 0.7157 g/liter= 40,532,734,383,110,650,203 grams = 40,532,734,383,110 metric tons [metric] (40.5 trillion metric tons).

somebody please check my calculations...

For comparison, the mass of the Earth's atmosphere is estimated at 5.3×10^18 Kg =5,300,000,000,000,000 ton [metric]

Scientists are beginning to see evidence that methane and CO2 release from thawing permafrost is a positive feedback result of the warming

NIAC has put out these calls once or twice a year since the late 90's. It's a cool organization, and I'm not saying that just because they've given me grants -- they've funded lots of really good work in many fields. Now if only NASA proper would follow up on more of it...

The NAIC website has a smidgen more info on it -- namely that there were four other research projects funded as well.

There's a PDF on this project that may contain more info, but my copy of Acrobat (6.0) declines to render the entire thing (or the PDF is junk, dunno which).

There's also an article on Astrobio.net that gives little more detail than the CU link... but it does have links to other sources that may be informative. Really though, this concept seems to be in such an infancy stage that "simple" questions like "so how do you turn it?" haven't been answered yet (in fact, in this NASA link how to keep the two craft in alignment is listed as a "main technological hurdle").

The NAIC website has a smidgen more info on it -- namely that there were four other research projects funded as well.

There's a PDF on this project that may contain more info, but my copy of Acrobat (6.0) declines to render the entire thing (or the PDF is junk, dunno which).

There's also an article on Astrobio.net that gives little more detail than the CU link... but it does have links to other sources that may be informative. Really though, this concept seems to be in such an infancy stage that "simple" questions like "so how do you turn it?" haven't been answered yet (in fact, in this NASA link how to keep the two craft in alignment is listed as a "main technological hurdle").

The NAIC website has a smidgen more info on it -- namely that there were four other research projects funded as well.

There's a PDF on this project that may contain more info, but my copy of Acrobat (6.0) declines to render the entire thing (or the PDF is junk, dunno which).

There's also an article on Astrobio.net that gives little more detail than the CU link... but it does have links to other sources that may be informative. Really though, this concept seems to be in such an infancy stage that "simple" questions like "so how do you turn it?" haven't been answered yet (in fact, in this NASA link how to keep the two craft in alignment is listed as a "main technological hurdle").

Multi-Billion dollar spelunking expeditions in outer space. What could we all POSSIBLY do with billions of dollars right here on Earth to benefit us all right now? Hmmm... alternative energy research? Nah. Cures for debilitating and deadly diseases? Nah. Improving the infrastructures of impovershed nations? Nah. Teaching people how to farm and improving their ability to do so to help keep them from satrving to death? Nah.

Yeah. Stupid NASA.

First, I will point out that I believe we landed on the moon. But a guy I worked with is a definite tinfoil hat conspiracy nut and it was pretty fun to listen to the theories.

To understand them, you have to distrust everything the government says and look for ways that it could be faked.

So how would we do it?

First, the mission would have been entirely unmanned. Land a radio transmitter on the moon and that solves the problem. Communications from NASA are sent directly to the astronauts on earth in "real time." The astronauts send their replies to the moon which echoes them back, thus giving the appropriate time delays. Same thing with the Apollo spacecraft.

I'm not sure about the triangulation properties, but consider that the first missions didn't go very far from the LEM. I'm also not sure if the Lunar Rover actually broadcast back to Earth or whether it sent to the LEM and from there back to Earth. If it's the latter, sure--we landed a transmitter on the moon. But the broadcasts stayed in one place.

Again, NASA had landed on the moon before Apollo--the Surveyor missions. So NASA did show it could land stuff on the moon.

It would be significantly easier to land a transmitter on the moon than it would be to land people there.

Why couldn't they dope it with lead or some other substance in the same way for the same kind of functionality on a better scale?

http://www.lpi.usra.edu/meetings/resource2000/pdf/ 7022.pdf

Quote;

Aerogels can become effective radiation shielding
by proper selection of the elemental composition: Silica
aerogels block UV and scatter X-rays while being
70% transparent to visible and IR wavelength. Incorporation
of heavy elements by diffusion or doping of
the porous solids can provide shielding from Gamma
rays or solar flares. Moreover, demonstrated phenomena
such as He densification in aerogel pores can be
exploited for liquid propellant confinement and increased
radiation shielding capability of the material,
thus providing an ingenious solution for two major
issues of planetary exploration.

Neko

Having looked at the "full resolution" JPEG, I see zero impact craters on the ice. Which is good, because we KNOW there is water ice near the poles (which is where this is), and it'd be really darn surprising to find water ice old enough to have impact craters on it. It should be relatively stable this far north, but not THAT stable--i.e., it's probably very young, as in still being modified by deposition and sublimation.

It's not news that water ice exists in north pole craters:
http://www.lpi.usra.edu/meetings/LPSC99/pdf/2026.p df

Was originally an Astronomy Picture Of the Day. (http://antwrp.gsfc.nasa.gov/apod/ap050720.html) This is a good site or backgrounds!

P.S. For other good/neat pics goto http://epod.usra.edu/archive.php3 (Earth Science Picture Of the Day)

There's only 10 more of the most recent NIAC phase 1 awards to trickle through the delay lines between the nodes of the blogohypersphere and find their way to /. as "news".

Or you can get it over with and read them all at http://www.niac.usra.edu/studies/studies.jsp?cpnum =05-01

You can also check the "call for proposals" link and wait until they open it up again, and send your Great Big Idea for consideration. Also, students can do the same, for scholarship money at http://www.niac.usra.edu/students/index.html

There's only 10 more of the most recent NIAC phase 1 awards to trickle through the delay lines between the nodes of the blogohypersphere and find their way to /. as "news".

Or you can get it over with and read them all at http://www.niac.usra.edu/studies/studies.jsp?cpnum =05-01

You can also check the "call for proposals" link and wait until they open it up again, and send your Great Big Idea for consideration. Also, students can do the same, for scholarship money at http://www.niac.usra.edu/students/index.html

if you go to nasa and use the search for "niac" the top few hits are dead links....way to go nasa
eventually, you will wind up here, which is a one paragraph proposal.

http://www.niac.usra.edu/files/studies/abstracts/1 147Smith.pdf
there does not seem to be more info available, even tho this is public money. totally inappropriate - that my tax dollars should be spent on ill described and secret research, the proposals for which are not even public.
does this mean any wanker who can pen a paragraph that sounds good can get 50K

Blame the title, and the editor that let it pass. I tried to tell them before release that it was wrong.

NASA will not research anti-matter rockets. NIAC (http://www.niac.usra.edu/ will fund an external investigation. This is the kind of thing that NIAC (NASA Institute for Advanced Concepts) does. They foster the dreamers.

It's very intersting stuff, but it's PRE-vaporware. It's not even a study yet. It's a brainstorm on paper to find out if the idea is worth making a study out of.

SOFIA - Stratospheric Observatory for Infrared Astronomy
http://www.sofia.usra.edu/

The hydrogen powered aircraft is definitely too small for the time being, but vibration is a problem that's already been solved.

Personally, I prefer the idea of controlling the global weather.

Putting aside the intricacies of controlling such a chaotic enviroment, the impact on an Englishman's typical conversation would be astounding.

Would we be able to adapt?

What would we talk about?

Personally, I prefer the idea of controlling the global weather.

Putting aside the intricacies of controlling such a chaotic enviroment, the impact on an Englishman's typical conversation would be astounding.

Would we be able to adapt?

What would we talk about?

Strangely, NASA does not give credit to the inventor of Artificial Metrorite Strike Spectroscopy. It was first published by Scientist and Science Fiction author Jonathan Vos Post. See: HUMAN AND ROBOTIC PRECURSOR MISSIONS TO THE POLAR ICECAPS OF MERCURY, Proceedings of The High Frontier Conference XI: Bringing the Vision of Space into Reality, 11th in a series formally known as the Space Manufacturing Conference, Space Studies Institute, Princeton, NJ, June 1993. Also cited in: "The Ball-bearing Bowling Alternative: Wild Strikes for Polar Ice", Mercury Messenger, Issue 6, July 1994] It was first suggested for the icy poles of Mercury, but was said to applicable for any airtless heavenly body. Sometime before the Mercury orbital insertion, the spacecraft would release a cluster of 5 "artificial meteorites" -- golf-ball- sized 1 kg spheres each of different dense metal rare on Mercury (Tungsten, Uranium- 238, Platinum, Gold or the like). These are spring- or pyrotechnically-released so as to separate from the spacecraft, not interfere with the spacecraft's orbital insertion, and be aimed to violently impact near the North Pole of Mercury. There being essentially no Mercurian atmosphere to slow them down, these spheres impact at various points, nearly simultaneously, at velocities approximately equal to Mercury's escape velocity of 3.476 km/s plus the approach velocity at the time of spacecraft separation. For back-of-the envelope purposes, let's estimate this impact velocity at 5.00 km/s. Each "artifical meteorite" at that velocity, with each weighing 1 kg, carries a kinetic energy of 1/2 mv2 = 0.5 kg (5x103 m/s)2 = 0.5 kg (25x106 m2/s2) = 1.25 x 107 kg m2/s2 = 1.25 x 107 Joules. Since 1 J = 0.2389 calories, each impact carries approximately 2.986 x 106 calories. Since it takes 1 cal to heat 1 g of water by 1o C, and 80 cal to melt 1 g of water ice at 0o C, and 498 cal to vaporize 1 g of water at 100o C in a vacuum, then it takes roughly 148 + 80 + 100 + 498 = 826 cal to heat 1 g of ice from -148o C to 0o C, melt it, heat it to 100o C, and vaporize it. Hence, if all the energy of each impact was used to vaporize ice, each "artificial meteorite" would vaporize 2.986 x 106 cal/(826 cal/g) = 3.615 kg of ice. In actuality, some of the impact would shatter ice, some would send fragments flying, and some would heat the water to a considerably higher temperature, i.e. into ionized gas (plasma). So, if all 5 spheres hit ice, we would get 5 bright flashes, each with a different spectrum. One would be of water with a trace of tungsten, one of water with a trace of gold, one of water with a trace of platinum, and so forth. Additional impurities in the ice would show as traces of other volatiles, such as carbon monoxide, methane, ammonia, hydrogen cyanide, cyanogen, and the like. The orbiting infrared CCD spectrascope could easily determine which of the 5 impacts struck ice, and what the chemical consituents of the ice were at each of the impact points. If the spectrascope were even more sensitive, we could release the same mass as a shotgun blast of 5000 1-g ball-bearings, and get a pretty good resolution chemical mapping of the polar caps.

Sure would be nice to have a space elevator. I'm having my doubts that this group of 5 full time and 4 part time people are going to have much to contribute. There is a lot of talk on their website about plans and research and 'groups', but very little substance. It seems their first priority was to develop a line of clothing and an online store. The "Finance" portion of their group consists of investment club opportunities which they generously offer to the public. I couldn't find any mention of other members of their "Group" apart from the sub-companies consisting of the same 9 employees. So far it looks like they have received some money from NASA and $100K from local development agencies in New Jersey where they have announced the building of their first factory. The money from NASA is a little misleading, however. It seems that another company, High Lift Systems, got its start when LiftPort's President, Michael J. Laine, ran into Brad Edwards on a space forum. Edwards is a physicist who worked at Los Alamos National Laboratories for 11 years and had raised $570K from NASA to study the feasibility of a space elevator. Laine originally wasn't interested - "I thought it was ridiculous,' says Laine" - but quickly changed his mind. Edwards is also the only scientist or researcher connected to LiftGroup on their website. Unfortunately for LiftGroup, but probably not for Edwards, after about a year he gave Laine the boot and went off to do research at Eureka Scientific under a NASA grant. Currently he has received $2.5M from the US government to fund his own lab. His take on Laine? He says that Laine "spins his wheels" and "if Michael Laine is standing there with something, Boeing and the Air Force won't even notice him."

LiftPort Group seems to be a lot of talk and a website. Search results for Laine are few and all related to LiftPort, yet supposedly he has been a leading proponent of the space elevator for years. Content about LiftGroup on other websites consists almost entirely of Liftgroup press releases, with no information other than that provided by LPG. LiftPort Group claims that LiftPort Carbon is a leading force in the industry and its product, Liftite(TM) carbon nanotubes, will "revolutionize the way the world thinks about materials". There is no third party reference to this not originating from LiftPort that I could find. As a matter of fact, I can not find ANY reference from ANY acknowledged authority in the field confirming any of LiftPorts claims. While other companies are mentioned in news stories about product releases, cooperative ventures, and funding awards, LiftGroup is mentioned in quotes from its own press releases. Maybe I'm missing a huge body of information somewhere, if not, the only question left seems to be...is Michael Laine a kook or a crook? I guess time will tell.

billy - who disavows all knowledge of THIS particular mission

Gosh, what next? The properties of fluids are the same on Earth and Mars.

I know you weren't really trolling, but seriously you need to reexamine your understanding of the scientific process.

The fact that there are dustdevils on mars isn't new - the scientists I worked with on MER had concluded that there were plenty nearby from satalite imagery (they seem to be formed often in craters and leave trails, as seen in some unreleased satalite imagery). We've had prior observations of effects of dust devils, as described in this paper, and even a few other movies (see bottom of page), but this is our first look *UP CLOSE*. (also of note is this satellite image from the Mars Global Surveyer)

The point here is not "we discovered dustdevils on mars, look pretty picture," the point is that the assumption that physics works the same on mars allows us to properly interpret this *much* better imagery of dust devils and come up with a lot of useful information about the atmosphere, wind speeds, grain size, etc.

I think this attitude of "gee whiz this isn't new" is why a lot of good science doesn't get funded these days. Just because something is "obvious" doesn't make it right, and just because an experiment or observation is not novel does not mean we have nothing to learn from it!

In the real world you also have to get out of Earth's gravity, fight against the Sun's gravity, and then push against Mars' gravity to avoid crashing.

You also have to consider that when leaving Earth, you still have Earth's tangential velocity, which is much greater than Mars' (via Kepler's third law). The best way to go from Earth's orbit to Mars' orbit is a Hohmann transfer (about 400 million km). Say an object in orbit needs to go to a higher orbit. You don't fire your thrusters against gravity, you fire them in the direction of your orbit. Of course it's impossible for a chemical rocket to fire that long; the heat buildup would destroy the engine. That's why all current missions get the necessary velocity in one quick push.

And of course the new technologies will be better, but they either don't exist or they are being tested (SMART-1 had several problems in it's 14 *month* journey to the moon). While NASA hasn't launched an ion-drive mission they most certainly *have* tested such engines, as well as the nuclear thermal propulsion engines. The problem is, as I said, economics. There's absolutely no reason to get a scientific mission to mars in a two week timeline.

Finally, when you say We should be testing new technologies, you make it seem like we aren't testing new technologies. For a list of just the projects that NASA is funding, check out the NASA Institute for Advanced Concepts That page shows projects working on all of the propulsion technologies you mentioned. Other independent researchers are looking into all of the concepts you mentioned, and more.

FYI: the wired article on space elevators (referenced in the first wired article) has a link to the NASA IAC, which contains a pretty cool technical report (PDF) on the specifics of the space elevator proposal. They cover a lot of their basis in terms of the technical details and possible problems from cable construction and deployment vehicles to oscillations in the cable and environmental concerns.

FYI: the wired article on space elevators (referenced in the first wired article) has a link to the NASA IAC, which contains a pretty cool technical report (PDF) on the specifics of the space elevator proposal. They cover a lot of their basis in terms of the technical details and possible problems from cable construction and deployment vehicles to oscillations in the cable and environmental concerns.

http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1741 .pdf

http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1741 .pdf

are in this this PDF document

Here's an alternative site with similar info:
LPI Lunar Resources
Low-tech slide show: Apollo Image Atlas

Here's an alternative site with similar info:
LPI Lunar Resources
Low-tech slide show: Apollo Image Atlas

You want direct evidence?

Sent a powerful laser beam to the moon, aimed at the landing sites of either Apollo 11, 14 or 15.

It will be reflected back.

http://sunearth.gsfc.nasa.gov/eclipse/SEhelp/Apoll oLaser.html
http://ilrs.gsfc.nasa.gov/satellite_missions/list_ of_satellites/lunar.html
http://www.lpi.usra.edu/expmoon/Apollo15/A15_Exper iments_LRRR.html

Yes you can, but the moon is about 2100 miles across

Even the best laser will disperse to a spot a few miles across on the moon. When it hits there, it needs to be bright enough to be visible here. and it needs to be much larger.

Imagine the moon as a circle 2100 pixels across. For the writing to be visible on earth, the illuminated line probably needs to be 25 to 50 miles across. And bright enough to shine back 235,000 miles. Mind you, the moon is about the size of your thumbnail when you hold your hand out in front of you. Think something with the resolution of a 48 pixel icon file, maybe less.

The proportions are easy enough to figure out. Then we get to the power requirements of such a beam.

Typical entertainment grade lasers for light shows are 5 - 20 watts, and can be higher power. If you want a spot 6 kilometers wide on the moon, then normal 6 mm wide beams (about 1/4) would have to expand 1,000 times the diameter, 1,000,000 times the area, and would have to be about 40 megawatts. 6 KM = 3.728 miles.

If you want a 60km spot then you are taking about 10 the diameter, another 100x the area, and so 100x the power for the dot to scale properly.

This means a 4 gigawatt laser to draw your pretty design on the surface of the moon. You could probaly get away with a simple Gigawatt laser. The only ones currently made are scientific research grade, and generate pulses in the nanosecond range. a 10 gigawatt laser to push a solar sail as a means of interpalnetary propulsion. There is also this interesting paper.

Corner cube laser reflectors left by the Apollo missions can (and are) used to measure the moon's distance from the Earth with the required accuracy.

See also http://www.gsfc.nasa.gov/scienceques2002/20030425. htm.