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The buzz among all of the media outlets that follow space exploration has been that a return to the moon is imminent. For the supporters of Robert Zubrin, the moon is anathema to their cause, a siren on the way to Mars. I happen to feel differently.
Humans have not ventured beyond earth orbit since 1972. In the years since then, only three of the many attempted landings on Mars have been totally successful. The human spaceflight endurance record was extended to 438 consecutive days, but this was only possible with the aid of supply ships to the Mir space station. Can we confidently say that we can land humans to Mars and have them survive the 910 day excursion? Losing Columbia and the 1999 Mars Probes gives me reason to pause.
The moon is a place where humans can work in reduced gravity, test life support systems that are truly closed, andbe within one to three days of home at all times. Perhaps Mars Direct, in the form of "Moon Direct," will enable a truly in-depth exploration of the moon. Successful moon missions will validate essential parts of Mars Direct or whatever method is chosen for going to Mars.
The moon holds the keys to the future of mankind's survival on earth. When the population reaches 10 billion by 2050, the moon's minerals will be ever more important. Further, the solar power collected on the moon will be vital to meeting the energy needs of mankind.
Mars fanatics, don't lose faith. The moon is not a detour, but a stepping stone to Mars in mankind's eventual colonization of space.
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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The moon holds the keys to the future of mankind's survival on earth. When the population reaches 10 billion by 2050, the moon's minerals will be ever more important.
What minerals does the moon have in abundance that are valuable enough for it to be profitable to mine them on the moon?
Further, the solar power collected on the moon will be vital to meeting the energy needs of mankind.
It would not make sense to use the moon to collect solar power for Earth unless the solar panels were produced on the moon with lunar materials, and there was an efficient way to transport the energy to Earth. Otherwise, satellites would be cheaper and more efficient. Even better would be to continue to use the Earth for solar panels; enough sunlight hits the Earth's surface to meet mankind's energy demands for a long time to come.
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Lunar solar power makes plenty of sense, as Dr. David Criswell (a leading proponent of the idea) recently testified before Congress. Solar panels would be manufactured from lunar materials because lugging the massive amount of solar panels to earth orbit (as seen in those fanciful space solar ower drawings) would be cost prohibitive. The power generated on the moon would be transmitted to earth in microwaves. Satellites orbiting the earth and moon could deflect some of these microwaves when the side of the night side of earth needs power.
Dr. David Criswell's testimony
The Industrial Physicist, a magazine that has printed articles on Lunar Solar Power
Who needs Michael Griffin when you can have Peter Griffin? Catch "Family Guy" Sunday nights on FOX.
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The moon is a place where humans can work in reduced gravity, test life support systems that are truly closed, andbe within one to three days of home at all times. Perhaps Mars Direct, in the form of "Moon Direct," will enable a truly in-depth exploration of the moon. Successful moon missions will validate essential parts of Mars Direct or whatever method is chosen for going to Mars.
The moon holds the keys to the future of mankind's survival on earth. When the population reaches 10 billion by 2050, the moon's minerals will be ever more important. Further, the solar power collected on the moon will be vital to meeting the energy needs of mankind
DR. Zubrin brought up a good point when he talked about Mars Direct.
Many components of the Mars Direct could be used to goto the moon, and it would be a good idea to work out the bugs on an extended moon mission, where SNAFUs can be fixed much easier.
Also, many bugs on unmanned craft would never be an issue on a manned spacecraft. With the ability to interface with computers and such, the human in space can often times thwart the bugs caused by the humans on Earth.
Radio Free Mars, audio of Dr. Zubrins testimony
If you haven't heard it, you should listen to Dr. Zubrins testimony. It also has a brief question/answer session.
We are only limited by our Will and our Imagination.
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Whether it's Mars or the Moon (preferably Mars), I just hope when we do finally go it's not just for show. No flags and footprints! The momentum is building for either one of the missions.
One day...we will get to Mars and the rest of the galaxy!! Hopefully it will be by Nuclear power!!!
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Zubrin has several times recently suggested that the Mars Direct equipment could be used for the moon as well, and the drift of reports from the White House is that a goal of returning to the moon must be done with more distant destinations (Mars, NEOs) in mind. So in a sense there is a convergence of views, with differences of emphasis.
Regarding lunar exports to cover parts of the expense of revisiting the moon, there are two I can think of:
1. Water in the polar regolith, IF it can be exploited. My guess is that it can. Some argue the trillions of tonnes of water should be left for future lunar inhabitants. This is possible, but strikes me as an argument similar to the one that petroleum should be left in the ground and extracted for petrochemicals only, not for energy, since it will run out. The amount of lunar water we will use as rocket fuel in the next, say, two centuries, would use up a small fraction of all the water there, and if its use results in cheaper space transportation and a larger lunar infrastructure, in the long term it benefits the moon. Put another way, it makes little difference if they have to import ice asteroids in 3350 versus 3450 AD, especially if the ice exports means the moon is bigger and more developed in 3350.
2. Platinum group metals (platinum, iridium, etc.) extracted from nickel-iron meteorites. I suspect it will be a long time before we can build robotic miners that can go to a nickel-iron asteroid, process the "ore" (the asteroid) to extract the parts per million of platinum group metals, then fly just them home. Otherwise, we have to haul the 99% of the asteroid that is iron, cobalt, and nickel back to low earth orbit, which is expensive and risky (one mistake and you wipe out a city or create a big tsunami). And then we have to process the materials in zero gravity, which is still unproven and probably complicated (gravity has its advantages where separation of materials is concerned; many separation processes rely on differences of density). It would be much easier to run a robotic regolith processor over the lunar surface, excavating the top two meters (which is mostly pounded to sand-size particles and gravel) and running it through a magnetic separator to obtain the nickel-iron particles. Then separatation processes using gravity could be used. Possibly the base would have to import some carbon if carbonyl processes are used, but human waste will provide that as well, and as long as the astronauts want to import filet mignon and wheaties--things they can't grow on the moon--there will always be carbon available. In fact, lunar agriculture will be much more expensive than Martian because of micrometeoroids and the 1-month day-night cycle, so a moon base may always be importing some food. The lunar base provides a preexisting facility to learn how to do platinum-group extraction that no asteroid has, and then the moon base will have experience and proven cost figures on its side. So my guess is that "asteroid mining" will start on the moon. Getting the processed stuff to the earth's surface requires a small rocket and a good heat shield, which should be much cheaper than the cost of flying stuff up the moon from the Earth (i.e., maybe $100 per kilogram once the transportatin system is developed).
As for Helium-3: maybe. We'll see. There's still no proof that fusion reactors can be built that are cheap enough to compete with other energy sources. That's the key question, not technical feasibility (which still hasn't been demonstrated either, after about 50 years of trying).
As for lunar electricity exports: I've seen some of the pros and cons. One problem that the plan suffers will be apparent tomorrow evening between 8:07 and 8:23 p.m.: eclipses. If the moon is in the earth's umbra between 4 p.m. and 6 p.m. Eastern time during the peak power demand on the East coast and during a heat wave when everyone has their air conditioners running, and the East Coast is getting 10 megawatts of power from the moon, what do you do? You don't build a 10 megawatt power station on the moon, that's what you do!
But the bigger problem is cheap solar power on the Earth. If it is true that 40% efficient solar cells are on the horizon, and that 50-60% efficient cells appear to be possible in the next few decades, why cover the moon with them instead of your house's roof? They're talking about making cells in designer colors and cells that are partially transparent. You could give your house new siding and the siding will make power for you; or new roofing and it will power for you; or new "tinted" windows and they will make power for you while admitting light into the house. There is preexisting demand for such cells--solar technology is taking off right now. Any robotic factory for stamping out cells on the moon (probably low-efficiency ones, by the way) could stamp out the same cells on the Earth with lower overhead and better productivity (because breakdowns and shortages of materials could be remedied immediately). So my guess is that the existing solar technology will favor production of power ON THE EARTH.
-- RobS
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Although the technology does exsist to get us to Mars, the kind of hardware needed to do more than science expeditions does not. In this reguard, a return to the Moon for good would permit these kinds of technologies to develop while being close enough to Earth to be supported by "traditional" methods in the mean time.
At least initially, a crewed Moon base would be very dependant on Earth for supplies and such, besides crew exchange, so it would force Nasa/et al. to get in the habit of REGULAR rocket launches, which would in tern demand better reliability which would get us to Mars more reliably. The Mars crew lander might be based on a flown-a-hundred-times DC-X like Moon lander... it has to work right the first time.
As far as stuff on the Moon reasource wise, that isn't going to happen... be practical people, how in the world are you going to get signifigant mineral mass back to Earth? Even getting it back from a NEA borderlines on nonsense economicly. The only thing on the Moon worth mining is water and Helium-3. What Lunar reasources are good for is making fuel to get us places... don't bring the wealth of the Solar System to the people of Earth, its too heavy, instead bring the people of Earth to the Solar System.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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i see no reason we can't do both, a la zubrin. he's recently suggested using a moon mission as a milestone in the development of the mars mission-- as long as the moon isn't the end in itself i'm all for it. at this point i just want to see SOMETHING start to happen.
but i think mars is the future-- especially considering the possible exobiological payoff, which is so far unmentioned in this thread.
then there's the public interest/PR angle... we've done the moon, less interest there for joe six-pack... but mars has a higher chance of failure which could be the last nail in the coffin of human spaceflight. so let's do the moon as a rehearsal for the big red enchilada. complimentary goals.
You can stand on a mountaintop with your mouth open for a very long time before a roast duck flies into it. -Chinese Proverb
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I agree that we should return to the moon first, as much as I want to see humans on Mars. The experience will be invaluable. And if we build a Gateway Station at lagrange 1 between the earth and moon, the technology for the interplanetary vehicle can be tested as well.
-- RobS
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Solar power from the Moon? Regretfully, I don't believe this for a second.
The only advantage that such installations would have would be the lack of an atmosphere. A factor of 2 for collecting energy at best. I can't see how major engineering on the Moon would be cheaper than just building a double set of solar panels on Earth.
In order to use indigenous resources for large scale panel construction, you would also have to reduce lunar silicon oxide into metallic silicon. The chemical reaction requires carbon and looks like this:
SiO2 + 2C = Si + 2CO
The Moon is essentially carbon free, so you would have to import the carbon in much the same way as water if polar reserves are unextractable, and although recycling is possible, a 100% return will never be achievable.
Beaming the energy 400 000 km by microwave will entail its own problems. The O'Neill Solar Power Satellite typically used a 1 km wide rectenna to recieve the energy on Earth. Keeping that size would mean a lunar transmitter 400 km in diameter!
Even if you reduced the size by a factor of 10, something which can be done by using a higher frequency - 30 GHz instead of 3 GHz - it's still nothing but preposterous, but then you would lose about half the energy to atmospheric absorption, thus defeating the only advantage lunar solar power would entail compared to Earth systems.
Of course, terran solar power, without the fantastic costs required for lunar construction, is in itself in no way competitive with nuclear power and fossile fuels. Like RobS writes, more efficient panels in "designer colours" could be deployed for household use, but what about the energy guzzling needs of industry and manufacturing, not to mention fuel cell based transportation of the future?
No. Why not build a series of advanced fission power plants instead? Safe, cheap and absolutely emission free as far as pollution and green house gases go. Non-recyclable waste could be buried in ancient bedrock, like the Scandics of Sweden and Norway for example (for a fee, naturally :;): ).
After all, fusion is on the horizon and then all of these problems are just about solved. We only have to keep going at a cheap high energy consumption rate in order not to stall progress. The future is nuclear; either that or it won't show up.
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This report suggests that there is probably far less lunar ice than many had hoped for.
Without plentiful lunar ice to fashion into rocket fuel, doesn't the allure of the moon diminsh considerably?
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This report suggests that there is probably far less lunar ice than many had hoped for.
Without plentiful lunar ice to fashion into rocket fuel, doesn't the allure of the moon diminsh considerably?
*I hardly find that surprising. The moon has little to nothing in the way of ice caps, and Apollo missions buzzed it up close and personal at least 7 times (Apollo 8 especially). I don't recall any reports of ice being seen (or detected by whatever means) in the valleys, craters, or shadowed sides of mountains on the moon.
Maybe I've missed some info along the way, though.
--Cindy
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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This report suggests that there is probably far less lunar ice than many had hoped for.
Without plentiful lunar ice to fashion into rocket fuel, doesn't the allure of the moon diminsh considerably?
It does. Damn it, Mother Nature, why can't you just work with us here for a change!
:angry:
On the other hand, the impression I got from the article wasn't that clear-cut. They concluded that radar signals bouncing of rocky (sides?) of one crater positively clear of H2O gave off a similiar radar signal as the original Clementine probe. Okay, so it could be rocks that Clementine had been sensing all along. The rest of their 20% sample readings were negative, but point of fact is that Clementine's wasn't.
A matter of interpretation?
Remember that two missions that actually went to Lunar orbit and studied the poles centrestage, one using radar and the other a neutron spectrometer gave off signals indicative of water and hydrogen respectively. If there's no polar ice where did the relatively large amounts of hydrogen come from? Not from pointed rocks, surely. Secondly, if there's only diluted water (0.5% spread out, worthless) as the article suggests could still be there, the Clementine radar probably would not have been able to detect it anyway.
Hopefully the ESA SMART-1 probe is properly equipped to spell it out for us in 2005. Till then we should perhaps sit tight and not jump to conclusions.
I hardly find that surprising.
- Me neither, Cindy. It's more of a hope that somehow might turn out to be right.
The moon has little to nothing in the way of ice caps, and Apollo missions buzzed it up close and personal at least 7 times (Apollo 8 especially).
- Of course you're right about that. As for the possibilty of ice/permafrost, albeit in small but purposeful concentrations, it's been on the agenda only since the mid 90's.
What wouldn't I give for an ice cap!
Addendum:
Earlier in the thread I wrote about water having to be transported to the Moon if there isn't any. This gave the wrong impression. As far as I know what you would have to ship to the Moon would really be hydrogen. By reacting it with the mineral ilmenite for example, which makes up as much as 10% of certain Lunar ores, water would be produced according to this scheme:
FeTiO3 + H2 = Fe + TiO2 + H2O
Part of the water could be further electrolyzed into H2 and O, serving propulsion and life support needs. Considering that Lunar dirt is almost entirely made up of various oxides, there are probably a number of similar mechanisms at hand.
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Arecibo used the same radar technique as Clementine; intriguing but not conclusive. The gamma-ray spectrometer on Lunar Prospector measured thermal and epithermal neutrons; it gave far more conclusive results. It's unfortunate that scientists aren't confident with the calibration of that instrument.
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RobertDyck, the gamma-ray spectrometer is a different instrument from the neutron spectrometer. Could you tell us if the gamma-ray spectrometer has any significance related to the water question?
I remember that you wrote an informed reply on the findings of the Lunar Prospector at some earlier time, but unfortunately I don't recall what thread it was.
Respectfully,
Gennaro
Website on the Lunar Prospector mission:
http://www.lpi.usra.edu/expmoon/prospec … ector.html
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The New Scientist article has puzzling statements that make me worried about its credibility and suggest someone needs to look at the original source: an article in Nature. The article sets up and knocks down a straw man. Here's the crucial paragraph:
"The new data does not rule out ice altogether. The experiment would only detect ice sheets more than a metre thick. Any thinner deposits, or small ice crystals distributed in the lunar dust, would have remained undetected."
NO One expected ice sheets in the shadowed areas a meter thick! All our discussion on this board has been of regolith with less than 5% ice, maybe less than 1%. So the first half of the article that kept talking about disproving "thick ice sheets" has disproved something no one expected.
But then the article quotes the team leader thus:
"Campbell estimates that, at best, a cubic kilometre of lunar soil would have to be processed to extract just a cubic metre of water, making it a very difficult and expensive endeavour."
This isn't disproving "thick ice sheets"; this is disproving the barest TRACES of ice in the regolith. How do we reconcile this contradictory data? Read the Nature article, if possible.
If there is no water on the moon, this does pose a challenge for lunar exploration and going to Mars, but nothing a nuclear engine won't solve. Hydrogen fuel is harder to make from the moon than water because you have to throw away 88% of the mass (the oxygen). I don't see a way to consume it all for breathing or oxiding regolith. There's not much point breaking down water, throwing away 88% of it, and using 11% for fuel; it's more efficient using the oxygen as well. But hydrogen can be lifted from the Earth for solid core engines.
-- RobS
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Oh, Cindy asked about the Apollo missions and their not seeing any ice in craters. The Apollo missions all orbited around the equator of the moon. They were literally a thousand miles from the poles, and the poles were never visible from the Command Module when it was in orbit around the moon.
-- RobS
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RobertDyck, the gamma-ray spectrometer is a different instrument from the neutron spectrometer. Could you tell us if the gamma-ray spectrometer has any significance related to the water question?
Huh, you're right. The gamma-ray spectrometer measured elemental abundance and searched for (among other things) titanium. My mistake, sorry. The neutron spectrometer searched for water. So much information to memorize, so many web pages, so little reliability to the internet. My reference pages to details of the X-38 and now TransHAB have disappeared. NASA appears to be bringing down those pages regarding ISS components that have fallen out of favour. However, the Ames Research Center web page for Lunar Prospector is still here.
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In order to EASILY do serious water/H2/O2 mining in the Moon, there will have to be signifigant quantities of ice. No meter-thick polar glaciers is no huge deal, but to have only barest traces would pretty well doom any kind of large lunar base or future colonization... I hope that the ice question is solved BEFORE Bush/Et al. decide to "do a Kennedy" for the Moon. Without ice at least for Lunar fuel, then anything more than a lunar cottage for a half dozen people becomes an extremely difficult proposition. If the idea is to build infrastructure without the nasty 1G earth gravity, then any plan to return to a waterless Lunar surface should be abandoned.
Oh yes...:
"There's not much point breaking down water, throwing away 88% of it, and using 11% for fuel; it's more efficient using the oxygen as well."
This would be true maybe if your rocket were carrying the water being broken down maybe, but its not if it is mined from Lunar ice. If you can make that 11% work with ~1000ISP in a NTR, then that other 89% is more mass you have to lug with you. Since you want to make your rocket as light as possible, oxygen is heavy, if there is any way you can avoid carrying it the better. The biggest reason why hydrogen is the perfect fuel is that its light, so you have to expend a minimum of thrust to push the reaction mass. Not to mention, the best LOX/LH engines only get around ~440ISP.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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RobertDyck, the gamma-ray spectrometer is a different instrument from the neutron spectrometer. Could you tell us if the gamma-ray spectrometer has any significance related to the water question?
Huh, you're right. The gamma-ray spectrometer measured elemental abundance and searched for (among other things) titanium. My mistake, sorry. The neutron spectrometer searched for water. So much information to memorize, so many web pages, so little reliability to the internet. My reference pages to details of the X-38 and now TransHAB have disappeared. NASA appears to be bringing down those pages regarding ISS components that have fallen out of favour. However, the Ames Research Center web page for Lunar Prospector is still here.
I am no web wizard, yet I believe google and other places keep mirrors or cached copies of web sites that may no longer be available.
Anyone have any ideas on finding the now defunct X-38 or TransHab websites?
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If there is regolith with 5% or even 1% ice, it's worth the effort to extract it. This definitely has to nailed down; it makes a huge difference how e go to the moon or even when we go back.
If the delta-vee you want to achieve is, say, 10 km/sec--which is quite a lot, more than you need for most Mars missions if you use aerobraking--ten tonnes of payload (tanks, engines, people, etc.) would require 64 tonnes of LOX/LH2 for chemical propulsion (7 tonnes of hydrogen and 57 tonnes of oxygen). Oxygen is very dense and easy to store compared to hydrogen; the hydrogen tank is twice as big as the oxygen tank even though it has much less mass of fuel. If, instead, you are using a solid-core nuclear engine with a specific impulse of 1,000 seconds (exhaust velocity, 10 km/sec) you need only 17 tonnes of fuel, BUT IT IS ALL HYDROGEN. It has to be derived from 153 tonnes of water. The tanks to store it would be twice as large as the tanks for the hydrogen/oxygen rocket, too. If you are making the fuel on the earth's surface, by all means make the hydrogen and haul it to orbit. But if you are making it in the moon, go with the hydrogen/oxygen rocket! You need less water and smaller tanks. The fact that you are burning about 4 times as much fuel is utterly irrelevant.
Maybe the best compromise is the LANTR engine. After you run the hydrogen through the reactor and it comes screaming out at almost 35,000 kilometers per hour, you add oxygen and the resulting chemical reaction. The result is water vapor shooting out your rocket at about 28,000 or 30,000 km/hour (specific imulse is something like 750 seconds, I think). A LANTR rocket would push 10 tonnes of payload to 10 km/sec using only 28 tonnes of water. If it can be developed, the LANTR concept seems best to me for the next 30 years or so, anyway.
-- RobS
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The New Scientist Article What bothers me is the fact that there is talk of 'no hick ice sheets' NOBODY thought there would be thick ice sheets. What bothers me even more is the timing of the article, it couldn't come at a worse time, now that 'they' are mulling the possibility to return to the moon. I can imagine Senate reading this and going 'Duh, there's no wather after all, what were those space-guys in the hearings trying to sell us?' It's not new for many people, but bad news for the future... Potentially.
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I am no web wizard, yet I believe google and other places keep mirrors or cached copies of web sites that may no longer be available.
Anyone have any ideas on finding the now defunct X-38 or TransHab websites?
Wayback Machine has been very useful to me, repeatedly, though it's sometimes a bit of a job to find exactly what you want...
Wayback Machine Note: it only works from around 1996
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Oh, Cindy asked about the Apollo missions and their not seeing any ice in craters. The Apollo missions all orbited around the equator of the moon. They were literally a thousand miles from the poles, and the poles were never visible from the Command Module when it was in orbit around the moon.
-- RobS
*Thanks for clarifying, RobS.
Here's some more info from today's Yahoo! headlines (brief):
http://story.news.yahoo.com/news?tm....1219235
Rxke wrote: "What bothers me is the fact that there is talk of 'no thick ice sheets' NOBODY thought there would be thick ice sheets. What bothers me even more is the timing of the article, it couldn't come at a worse time, now that 'they' are mulling the possibility to return to the moon. I can imagine Senate reading this and going 'Duh, there's no wather after all, what were those space-guys in the hearings trying to sell us?' It's not new for many people, but bad news for the future... Potentially."
*I tend to disagree. You are indicating you think there's something suspect in the timing of this news? Anyway, I've never thought moon colonies, etc., were very feasible anyway (no atmosphere, very very low gravity, etc., etc.). I think this likely will turn out to be a good thing, as Mars exploration goes (on to Mars!).
--Cindy
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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