Slashdot Mirror
NASA Says Moon Has More Water Than Great Lakes
jerryjamesstone writes "The US Great Lakes have some competition: the moon. Yes, that old thing in the sky may hold more than all of the water contained in the Great Lakes, according to a NASA-funded study. From the article: 'Scientists at the Carnegie Institution's Geophysical Laboratory in Washington, along with other scientists across the nation, determined that the water was likely present very early in the moon's formation history as hot magma started to cool and crystallize. This finding means water is native to the moon.'"
Volume of the Great Lakes ~22.5 *10^3 km^3 Volume of the Moon ~21.9 *10^9 km^3 So, the Moon contains even more than one teaspoon of water in 5 tonnes of rock.
Well, they got a border on all of them... except Lake Michigan! USA!
It's not called the dark side because it's dark. It's "dark" because that side never faces Earth. Thus, during a solar eclipse the "dark" side is completely illuminated by the sun.
My office has been taken over by iPod people.
More importantly: Can you go sailing on it? Swim in it? Fish salmon, trout, and invasive asian carp from it? Ride a scooter along hundreds and hundreds of miles of it?
If not, I'll stay here in Michigan, the Great Lakes State.
We're Bi-peninsular and Proud.
Yes! Michigan!
(This message has been a public service announcement, brought to you in cooperation with the Michigan tourism office and my summer travel plans.)
http://alternatives.rzero.com/
Yeah, it gives me a case of the facepalm every time I see it as well. GSO is 42,164 km away, ala wikipedia. Call it 4.2x10^7 meters. The only material close to being possible to use for a cable are carbon nanotubes. Lets make a thread of a carbon nanotube cable, which does not exist in lengths more than like 30 cm at the moment, with a diameter of 1mm. That is an area of 3x10^-6 m^2, and results in a volume of about 132 cubic meters. This is over 50% more than the shuttle can hold.
Assuming we could go get an asteroid, a very, very large asteroid, and put it into GSO without either skipping it off the atmosphere or turning a city into a crater, we're left with the issue that we can't get a tiny, continuous cable into orbit with any current technology. The shuttle comes in 50% too small, and doesn't get to GSO, even Falcon 9 only has cargo volume of 14m^3 to GTO!
The next option is to somehow attach 1x10^9 30 cm sections of nanotube together, in a way that doesn't weaken them. That doesn't exist. We'd also have to be able to do this in space, since we can't realistically get a continuous cable up there.
So the only things stopping a space elevator are:
1) 1x10^9 carbon nanotube units short of reaching GSO
2) No way currently to move a large asteroid into GSO safely, nor many nations willing to let someone try for fear of an extinction event.
3) No way to get a continuous cable into GSO, despite the problems of #1
4) No known way to stick 1x10^9 chunks of carbon nanotube together effectively, preserving their high tensile strength. In space.
5) Current climber technology is shooting for 1km. That's only 42,163 km short of GSO.
6) Coincidently, the earth's circumference is about 40,000 km. Have we ever built ANYTHING on the scale of the earth's circumference? Have we ever tried to stress-test a cable of more than a km or two?
Sure, we could shoot for a continuous, 0.1 mm diameter cable, and that might fit on Falcon 9 and be possible to bring to GSO. But again, we're left with the problem with the asteroid, the climber, and stress-testing and QCing a cable that we can't build in a billionth of that length at a time, longer than the circumference of the earth. Or we somehow come up with a way to bond nanotubes together in a way that preserves their tensile strength, in space, with the ability to test and QC the work, and we're only left with the asteroid and climber issues....
Magic is unlikely to be better to research, but not by a lot...
Velociraptor = Distiraptor / Timeraptor