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No Ice on the Moon
eldavojohn writes "In 1994, there was speculation that there might be a southern ice cap on the moon — something our exploration of it could take advantage of. Unfortunately, recent evidence has come to light revealing that this probably isn't true." From the article: "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 localized 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." Well, it looks like we're going to have to hit Hoth before we hold that kegger on the moon."
I live in WV and have seen the Green Bank Telescope. Impressive radio telescope. Not as impressive as Arecibo though. I was expecting more like an array but it really is just one giant dish.
Better link than in the story:
http://www.gb.nrao.edu/
B.
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Sometimes stories just go back, and not forth. I suspect this is one of them.
Back in the Apollo days, a Saturn V third stage was allowed to smash into the moon so seismographs could pick up the vibrations. This and other tests allowed scientists to get a basic idea of the moon's interior structure. A core or crust of ice would have been pretty obvious. If there was any ice, it would have to be just traces.
Our instruments are getting increasingly better. This is a case of a hypothesis based on observations by a crude instrument being disproved by follow-up investigations by more sophisticated gear.
I'm disappointed, but hey, the universe wasn't designed to things easy for us.
Gold is economical to extract from ore that has less than one ounce of gold per ton.
Water is going to be more valuable than gold to someone on the Moon.
Water is way easy to extract.
It'd be a real bummer if this research proves true, because having water readily available on the moon would be a help in our (looong-term) future plans.
But, that doesn't mean that there can't be a whole lot of ice there someday. In the future, about the time when interplanetary travel becomes feasible and large quantities of water are needed, we will also have the technology to go out and capture water. One of the great motivations for interplanetary travel is mining asteroids for their abundant mineral wealth. Some consider capturing and towing an asteroid into Earth orbit for better availability. Why not capture and tow a water-rich comet, too? If there are grave concerns about it hitting the earth, just bring it very slowly towards the moon and orbit it there. It would be easily accessible there from the moon and from spacecraft, much higher in Earth's gravity well than LEO.
This is hardly a new idea - I think Arthur Clarke was a big proponent of it. I'm not advocating that we try it out in the next few years, either - I'm just saying that getting water to the moon, by the time we need lots of it, isn't that farfetched.
After reading this article, I feel like when you used to watch Spock look into his mystery screen and make pronouncements about just about anything. "Captain, the enemy captain is wearing green boxers!"
/moon/ pick it up somewhere else, and know that there is no water there. Damn amazing to me.
We bounce some radar off of the freaking
Steve
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Thomas Gold used radar studies to show that the surface of the moon was made entirely of soft dust which an astronaut would sink right through. And he was right. The top millimetre of the moon (which is all the radar could see) really is like that.
A highly oblique illumination of the lunar south pole from 4000000km away can not prove that there is no ice on the moon. Ground penetrating radar from orbit or the surface will prove that to a certain depth.
Its worth noting that the control samples which apollo astronauts took from under the LM descent stage failed to show any volatiles at all, despite the fact that they had been gardened by the engine exhaust. There could be water on the moon and we wouldn't see signs of it elsewhere.
http://michaelsmith.id.au
As comets approach the sun, they develop a tail, caused by the solar wind. If you keep a comet "tethered" in orbit around the earth, it is going to be constantly eroded by the solar wind, and the earth will be bombarded by the crap falling off whenever we are "downwind" of it.
If it was in orbit around the moon, the same would happen, which may or may not be a useful way to get the comets contents onto the lunar surface. But it would be quite inefficient, as the percentage of time where the tail would hit the moon would be quite low. So unless you kept motors running to hold it always in the same position relative to the sun you would lose most of the material to space. Motors add inefficiency.
All this is assuming you could capture a comet in the first place. The inertia alone would mean you would have to gradually change its orbit, and that could take thousands of years to get it where you wanted it, and have a massive fuel supply to keep adjusting the comets course over that time.
I think that we have more efficient ways already available to get water to the moon, they are just expensive. Time is an expense too, so if you need something now, it's usually more costly.
OTOH, it might be worthwhile attaching a craft to a comet as it passes us, and adopting its orbit long enough to extract a supply of whatever chemicals/gases we can, and using them as fuel for longer distance travel.