Hi David!
Let me think straight out of my blue hat here.
First. the 'bending' you talk of is of course a result of the chosen map projection.
Looked at from space, the earth is half sunlit and half unlit. Period.
And the diffuse line between day and night a straight line dividing the globe in half.
So to visualize the lit side of the earth, one could try placing a circular object on a world map, with half the earths circumference (20 000 km) as diameter and centered where the sun is in zenith at a given time.
However, when I tried that, the thing completely blew up and became a zeppelin when I tried to move it about.
I cannot figure out why. Does someone see the flaw in my reasoning?
As a side note: some time back an image appeared on the net, supposedly taken from a space shuttle, showing the day/night line and how cities were lit up on the dark side.
The image was an obvious fake, and one thing that gave it away was that the shadow line bent away from the northern pole.
Another thing was that you could see the seabed structures of the Atlantic ocean.
Read more here http://www.snopes.com/photos/sunset.asp
Hälsning / Best regards Mats.E
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Sänt av: [EMAIL PROTECTED] 2006-07-31 10:22
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Here is a quick one before I go off & reinvent the wheel.
Has anyone seen a method of creating a table that will show the night time half of the
world in shadow & the day time untouched? Maybe some massive polygon that shades
half the world?
As I am using WGS-84 maps I can easily whip up a straight line that is correct at the
equator, but it would be nice to have something that bends properly, like is seen here:
http://www.elanware.com/
Thanks,
Dave
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