Skip to comments.Ice store at Moon's South Pole is a myth: study
Posted on 10/19/2006 6:41:12 AM PDT by presidio9
Hopes that the Moon's South Pole has a vast hoard of ice that could be used to establish a lunar colony are sadly unfounded, a new study says.
In 1994, radar echoes sent back in an experiment involving a US orbiter called Clementine appeared to show that a treasure trove of frozen water lay below the dust in craters near the lunar South Pole that were permanently shaded from the Sun.
If so, such a find would be an invaluable boost to colonisation, as the ice could be used to provide water as well as hydrogen as fuel. NASA is looking closely at the South Pole as a potential site for the United States' return mission to the Moon, scheduled to take place by 2020.
But a paper published in the British science journal Nature on Thursday by a US team says the Clementine data most probably was misinterpreted.
Donald Campbell of Washington's Smithsonian Institution and colleagues collected radar images of the Moon's South Pole to a resolution of 20 metres (65 feet), looking especially at Shackleton crater, which had generated most interest.
The team found that a particular radar signature called the circular polarization ratio -- which in the Clementine experiment was taken to indicate thick deposits of ice -- could also be created by echoes from the rough terrain and walls of impact craters.
The signature was found in both sunny and permanently shady areas of crater, which suggests that the reflection comes from rocky debris, not thick ice deposits.
If there is any ice at the South Pole, it probably comes from tiny, scattered grains that probably account for only one or two percent of the local dust, the authors suggest.
"Any planning for future exploitation of hydrogen at the Moon's South Pole should be constrained by this low average abundance rather than by the expectation of localised deposits at higher concentrations," the paper says soberly.
The research involved sending a radar signal from the Arecibo telescope in Puerto Rico. The signal hit the southern lunar region and the reflection was picked up by the Green Bank Telescope in West Virginia.
Now I'm not so sure either. I must have had "Moon" on the mind. I guess that makes me a lunatic.
What's the water for? Well, for life support, or for electrolyzing into propellants--you need LOTS of power for that--and then you have to lift the propellants back into orbit. Any payoff comes from the more modest gravity well of the Moon.
The payoff--if there is one--is S-L-O-W.
First, the sun is readily available as the base source of consumable energy. Fairly unlimited supply.
Second, whether we breathe it or burn it, the oxygen and hydrogen are not lost, they are transferred to a new compound, CO2 and H2O. The basic law of conservation of matter. Transforming them back into oxygen and hydrogen is again a question of the application of energy.
The supply of base elements is the major factor in living on the moon, not the supply of energy. Energy provides the means to manipulate the elements as needed.
It might be of interest to note that the moon appears to be 30% oxygen by weight. The missing element is hydrogen of which there are traces only.
If we added Mercury (which is denser than Mars but smaller obviously) to Mars, the little virtual calculator gizmo I've got here puts the combined mass at 9.7219E23, which is 16 per cent of the Earth's. Venus' mass is 81 per cent that of Earth. There really isn't any way to find enough material to make Mars like the Earth.
If there were lots of water available to bring Mars' mass to that of the Earth (and there could be), Mars could be converted to a planet with a planetary ocean, Earthlike atmosphere (synthesized from frozen gases imported from the outer Solar System, which is where the water could be lurking), and floating cities for humans. The final diameter of water-covered Mars would be larger than that of Earth, because of lower density.
Current Mars is just under 11 per cent the mass of Earth. Moving nearly 90 per cent of the Earth's mass is well in the future. IOW, the only practical prospect for the foreseeable is to build habitrail-style habitats on Earth (could be just inflatable structures) and deploy them on Mars, inflating them with the Earthlike atmospheric mixture, and staying indoors. :')
You mean there's no ozone hole on the moon?
The moon is an entire ozone hole. Pole to pole.
and staying indoors.
The taco stand and the fruit market, however, are still open for business.
So get out to the outer system and lob huge chunk of ice from Saturn back to the moon.
It's only 100K to send from Earth because the USA lacks the will to use better systems.
That is a fun one, but the dialogue is a joke (even in the context of an over the top tongue in cheek scifi spoof), is way too vulgar, the plot makes no sense, and there's an excess of bloodshed. Okay, so, it sounds perfect...
I can remember it for you wholesale.
As others have pointed out, this is both cost prohibitive and difficult from the bottom of a gravity well like Earth. As Kirkwood suggested the best plan is to get available water/ice someplace else in the solar system and deliver it to the Moon. A comet is a clear possibility, but there would be huge energy management issues. Those suckers are moving and getting one to impact without messing things up would be a trick.
I've read a good bit about the expected composiition of the asteroids in the main asteroid belt and there's supposed to be a lot of recoverable water/ice there. Getting out to the asteroids should actually be easier than landing on Mars. I think we'll do the belt first, then think about whether we really need to bother with Mars, except for scientific purposes. There's supposed to be a lot more in the belt that should be easy to recover, including lots of elements we may need alternative sources for as more and more terestrial resources get used up or, more likely, locked up by environmental regulations or our political or economic rivals. And there are supposed to be both precious metals (gold, platinum) and exotic elements, even things we've only made small quantities of in labs, in abundance. I want us to go there ASAP and I think that's where the commercial ventures with vision will first strike it rich.
Plus, once we get the knack of going out there and moving those rocks around they will make dandy presents to drop on those political and economic rivals. Particularly the big iron ones, with just the right targeting equipment. "Smart rocks," in other words. They make really pretty holes and there's no nasty radiation to bother everyone.
See you at the party Richter!
Smaller, shaped objects (perhaps made of tungsten) would be better, because they could be parked in their orbits such that the timing, trajectory, and targeting would be perfect, one behind the other. Despite no radiation, large impacts have much the same deleterious effect on climate.
If Moon could make an ice store work at the South Pole, he's a marketing genius.
I thought we already knew that the good Reverend was a marketing genius.
The idea is popularly known as "Rods from God," and Jerry Pournelle was an early proponent of the idea. I got the chance to discuss it briefly with him one of the times we ran into each other at Comdex, when that was still going on in Las Vegas. He's one of my favorite science fiction authors, along with Larry Niven, but Pournelle is also one of the very early PC columnists, going back to the very beginning in the mid to late 70s with kit PCs. I used to see him at least once a year from '77 on when I got involved in the first sales of pre-built PCs out in San Francisco. He was always very nice and generous with his time.
In addition to being an SF author and journalist he was also a member of Reagan's advisory panel that came up with the pieces of SDI. These kinetic energy weapons were considered as a viable weapon at that time as well, seperate from the SDI developments as this implementation doesn't deal with missile defense. There are kinetic energy parts of missile defense and their development is pretty much all that's left of SDI, except for the airborne laser, which should be available relatively shortly, and THEL, which we co-developed with the Israeli's. Rumsfeld was around back in the Reagan administration too and he's revived this version of the "Rods from God" specifically with the idea that they can be utilized against heavily dug in facilities, such as in Iran and North Korea. This 2005 article from The Weekly Standard covers that and other points about the system nicely.
Despite no radiation, large impacts have much the same deleterious effect on climate.
There are lots of sizes of rocks to drop. You choose the size depending on the effect you want. For me the point is that once we can move the asteroids around and mine materials from them we don't need to loft anything from Earth, even if we want to implement the "Rods from God" idea. We can get the material from mining the asteroids, or simply grab a rock of the right size and of a good enough shape and material to give us the effect we want. Pournelle and Niven used the idea extensively in their novel Footfall, from 1985. I think that is the ultimate "someone invades the Earth" book. They covered the topic of a natural comet impact in Lucifer's Hammer, from 1977. It has a fabulous description of the comet impact using the analogy of a huge hot fudge sundae. If anyone wants I can post that. I've already posted probably a lot more than people want to slog through and it's about 1,500 words, or 4 pages in Word. But it's a hoot.
"Howdy, stranger! If things have gone wrong, I'm talking to myself, and YOU'VE got a wet towel wrapped around your head."
"They're all connected!"
[from one of at least three Star Trek connections]
They covered the topic of a natural comet impact in Lucifer's Hammer, from 1977.I read that. It was about as much fun as an after-the-deluge kind of book would be expected to be. :') With SpaceWatch, the only way such a scheme could succeed and perhaps be explained away as a fortuitous accident would be to keep the projectiles small. Aerodynamic tungsten projectiles would get through the atmosphere and deliver a nice sized bang, destroying a population center while minimizing regional effects. He wrote, cheerfully. ;')
They also have an Orion spaceship. The character meant to represent Jerry Pournelle explains that kind of ship this way:
"Take a big metal plate," Curtis said. "Big and thick. Make it a hemisphere, but it could even be flat. Put a large ship, say the size of a battleship, on top of it. You want a really good shock absorber system between the plate and the ship.
"Now put an atom bomb underneath and light it off. I guarantee you that sucker will move." He sketched as he talked. "You keep throwing atom bombs underneath the ship. It puts several million pounds into orbit. In fact, the more mass you've got, the smoother the ride."
And when they built it and finally launched it they described it this way in the book:
Commander Kennedy whooped. "They made it! They're up! It's--"
"--first bomb fails you just start over."
"If the second bomb fails, you're already--"
"--already in the air. You'll fall. They're on their--"
"--way, by God! You can give me that drink now."
God was knocking, and he wanted in bad.
If you enjoyed Lucifer's Hammer then read Footfall. I think it's even better. Remember Harry the mailman? I really enjoyed that character. Well, they have a similar character in Footfall, Harry Red, an ex-biker / minstrel (he plays guitar and sings in bars to get drink and gas money). Really enjoyable.Well, I didn't really. The weepy diabetic guy's moral of the story, and the goofy alliance with the Soviets sound like unfettered gloomy Pournelle. Larry Niven's the wit of that collaborative team, which is why I enjoyed "Ringworld" and "Ringworld Engineers". :')
One of the things I really like about Niven is that a lot of his stories take place in one reality, which has been dubbed Known Space. It stretches from just a little in our own future, particularly with lots of stuff about Belters, the first independent humans who set up a society and industry off of Earth, to the far future of Ringworld and related stories. And he brings back events or references, as well. Of course, it also limits him (mostly) to the things he's established in earlier stories.
And it's not fun sex, it's forced or obsessive or strange.Hey, fun is relative. ;') It wouldn't surprise me that (like all of us, alas) Niven's done his best stuff and is in decline. But after all, having a career as a writer requires the luck of Teela Brown. ;')
One of the things I really like about Niven is that a lot of his stories take place in one reality, which has been dubbed Known Space. It stretches from just a little in our own future, particularly with lots of stuff about Belters, the first independent humans who set up a society and industry off of Earth, to the far future of Ringworld and related stories. And he brings back events or references, as well. Of course, it also limits him (mostly) to the things he's established in earlier stories.He's got a coherent fictional universe. :')
regarding what RightWhale said at message 56:
Hubble Telescope Turns to Moon and Sees Possible Oxygen Source
NY Times | October 20, 2005 | WARREN E. LEARY
Posted on 10/20/2005 12:58:40 AM EDT by neverdem
Breathing Moonrocks The Moon has plentiful oxygen for future astronauts
science.nasa.gov | Dave Dooling
Posted on 05/06/2006 5:39:58 PM EDT by Iam1ru1-2
One small breath for man (extracting oxygen from the lunar soil)
Daily Mail (UK) | 5/28/2006 | ELANOR MAYNE
Posted on 05/28/2006 4:25:09 PM EDT by Dark Skies