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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.'"
and Neptune has more water than Great Lakes.
The world belongs to those who get up early. - I'm far from being the king of Earth then
"The largest lake entirely within Canada is the Great Bear Lake. None of the Great Lakes are entirely in Canada, so none of them count. The deepest lake in Canada is Lake Manitou, which has an island inside it, and in that island there is a lake. That makes it the largest lake that's in an island that's in a lake in the world."
Though, I would expect people living next door to the US to be used to its "US is the world" attitude by now.
Preposterous, but now I'm curious! (Caution: I've only had one cup of coffee so far this morning, so please check my math!)
Depth of covering the moon with the contents of the Great Lakes, just once:
So, approximately 0.6 meters (just under 2 feet)!
If we use BooksInLoC of Great Lakes, that works out to:
So, to answer the original question: 17,400 Km (or approx. 10,800 miles) deep!
P.S. This was a fun exercise... I knew the Great Lakes were "big", and I knew the Moon was "big", but to think the Great Lakes alone could cover the entire Moon to a depth of about 2 feet... Just. Plain. Wow!
Extra Credit Question: If the moon were entirely covered by the water from the Great Lakes, how much brighter would it make a Full Moon seem on earth? Bonus: how bright is that compared to the Sun at noon?
The surface area of an ellipsoid (in this case, the moon) expands as it's diameter increases. Therefore, your math is off by more than a little bit.
According to Wikipedia, the moon has a mean radius of 1,737.10km and has a volume of 2.1958E10 km^3.
From your calculations, the great lakes have a volume of 22,560 km^3. Therefore, the volume of the great lakes times the number of books in the library of congress is 6.5424E11 km^3.
If we add this volume to the volume of the moon, the volume of our new moon is 6.76198E11 km^3. Assuming the new moon takes on a spherical shape, we can get the new radius of the moon by using the formula for the volume of a sphere, V=4/3r^3. Therefore, we deduce that the new radius is 7,974.65km.
Further assuming that the moon as it exists now settles in the center of this new waterworld relatively undisturbed, with it's mean radius remaining at 1,737.10km, we can calculate the mean depth of the water on the moon as 6237.55km.
Football fields doesn't even bother me as much. At least it's a specifically known number (100 yards - and yes I'm going with the American/gridiron definition of football because we seem to be the only ones who measure in football fields :)) that is small enough to wrap your head around.
Great lakes? Ok, I know they're pretty big, but I don't know if there's hundreds of thousands of gallons, millions, billions, trillions, or even more gallons of water in those things. I just have no sense of it. Same with "Libraries of Congress". I have no clue how many books they have. I know it's a lot, but I don't know how many. Biggest library I ever saw was our college library; it was 5 stories which compared to our little ~6000 sqft county library back home seemed ENORMOUS, but other students constantly expressed how small and sucky our library was so maybe even that is small potatoes in comparison.
People seem to be attached to using stupid units though. Kinda like that relative who insists in telling you distances in units of time rather than length.
"People who think they know everything are very annoying to those of us who do."-Mark Twain