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To: dr_lew
Terra's orbit... roughly 16 light minutes, reduced to 8". I'm going to call that 2 light minutes per inch. My pencil uses 0.5 lead(which is graphite). And it's unit of measure is mm, so convert back to imperial, and you get 0.019685 inches for the pencil line width.

So... 0.019685(2*60*C)... yeah. that's a wide line.

Cook math. It's all I got.

/johnny

31 posted on 10/28/2012 10:38:03 PM PDT by JRandomFreeper (Gone Galt)
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To: JRandomFreeper

I follow you up to 0.019685” = 0.5 mm . Not so sure what 2*60*C signifies.

The idea is that the eccentricity of earth’s orbit is 0.0167, but this is the “off centeredness”, which is the distance of the focus of the orbit from the center, in terms of the radius, or more precisely, the semimajor axis, and a circle shifted by this amount gives an excellent approximation to earth’s orbit. Considered as an ellipse, the minor axis is sqrt( 1 - e^2) times the major axis, or approximately ( 1 - 1/2 e^2 ) or (1 - 0.00014)

But 0.00014 X 8” is 0.001” which is to be compared to the pencil line width of 0.02” . So when I say “easily”, I mean that the pencil line width is twenty times as great as the difference between the major and minor diameters of the earth’s orbit, accurately drawn.


35 posted on 10/28/2012 11:09:13 PM PDT by dr_lew
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