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= 70 acres and a marble = = 212 acres and a marble =

212 acres and a marble

Picture will go here

Here is a little blue marble, painted with little green continents. The green continents, and transparent ocean, represent the distribution of life on earth. Though life started in the oceans, life is relatively sparse in them, occuring mostly around nutrient upwellings. The rest of the ocean is almost lifeless. The land has much higher biomass per square meter, even in regions like the Mojave desert. So, besides the ice caps and mineral deserts like parts of the Sahara, the land represents plant life, and the food chain that depends on it. The marble is pretty accurate as a representation of life.

The marble is 2.20 centimeters (0.866 inches) in diameter. The earth is 12,742 kilometers in diameter, 579 million times bigger. The earth intercepts 174,000 terawatts of energy from the sun. On average, about 20,000 terawatts of that energy is captured by land plants, from rain forests to the soil microbes of the Mojave. Most of that captured energy drives chemical processes in the plants, but about 200 terawatts becomes food and fiber, which feeds animals and microbes and fungi. While used by animals and fungi is small, these organisms are the recyclers of nature, converting dead plants into the materials to make more plants.

The sun puts out 384 trillion terawatts. How much is that compared to the earth? 2.26 billion times the energy shining on the whole earth - the rest blows out into empty space, never to interact with matter again. A tiny fraction might be visible as starlight on other worlds, but beyond 60 light years, the sun would only be visible with a telescope. It is very unlikely that the light of the sun matters to anyone or anything besides life in the solar system.

The cross section of the marble is 3.8 cm2 ( 0.588 in2 ). 2.26 billion times that is 86 hectares (212 acres), or a square of land 920 meters on a side.

Lower Central Park

86 hectares is the area of New York's Central Park, below 72nd street. The squiggly street near the top of this photo connects to 72nd street.

212acres (last edited 2013-01-31 00:08:27 by KeithLofstrom)