Enough sulfur to build 30 quintillion people (was It takes a lot of nitroge)

--- In spacesettlers@yahoogroups.com, "brooksn" wrote:
> --- In spacesettlers@yahoogroups.com, "hitssquad" wrote:
> > People make food
> People don't make food

Then there must not be more than 10 million people on the planet. Here's a history of human population, according to Wikipedia:

"
Estimated world population at various dates (in millions)

10,000 BC 1
9,000 BC 3
8,000 BC 5
7,000 BC 7
6,000 BC 10
5,000 BC 15
4,000 BC 20
"

Human food production (e.g. "people making food") began around 9,000 BC:
http://en.wikipedia.org/wiki/Neolithic_Revolution

The facts don't seem to be jibing very well with your theory.

> > There's only 12e18 kilograms of nitrogen on the planet (4e18 in the atmosphere, and 8e18 in the crust and mantle). At 12 kg per person, that's enough to build only 1 quintillion people, allowing each 2 kg for protein, with 10 kilograms left over for 500 cubic feet each of 10-psi atmosphere.
> I would think sulfur or phosphorous would be more limiting

http://chemistry.about.com/cs/howthingswork/f/blbodyelements.htm

"
99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.

1. Oxygen (65%)
2. Carbon (18%)
3. Hydrogen (10%)
4. Nitrogen (3%)
5. Calcium (1.5%)
6. Phosphorus (1.0%)
7. Potassium (0.35%)
8. Sulfur (0.25%)
9. Sodium (0.15%)
10. Magnesium (0.05%)
11. Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%)
12. Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts)

Reference: H. A. Harper, V. W. Rodwell, P. A. Mayes, Review of Physiological Chemistry, 16th ed., Lange Medical Publications, Los Altos, California 1977.
"

Based on the above, a 70 kg human would require .7 kg of phosphorus, and .175 kg of sulfur. If the earth's crust contains 40 trillion tonnes of uranium, then, based on this:
http://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth's_crust

...it also contains 1,050 ppm / 2.7 ppm * 40 trillion tonnes = 15.5 quadrillion tonnes of phosphorus, and 350 ppm / 2.7 ppm * 40 trillion tonnes = 5.19 quadrillion tonnes of sulfur. That's enough phosphorus to build 1.55e19 kg / .7 kg per person = 22.2 quintillion people, and enough sulfur to build 5.185e18 kg / .175 kg per person = 29.6 quintillion people.*

That's a lot more people than could be built with Earth's nitrogen supplies. Using all the nitrogen in Earth's atmosphere would allow the construction of only 2 quintillion people -- and there would be no nitrogen left over for air without dipping into the nitrogen in the crust and mantle. Using all the nitrogen in Earth's atmosphere, crust, and mantle would allow the construction of 6 quintillion people, but again none would be left over for air.

*If we consider the entire lithosphere (which includes the solid parts of the mantle, as well as the crust):
http://www.madsci.org/posts/archives/1999-11/943288749.Es.r.html

...(1.365e23 kg) there's enough sulfur (500 ppm of that, or 6.825e19 kg) to construct 6.825e19 kg / .175 kg per person = 390 quintillion people -- or over a third of a sextillion people.