A friend of mine, Mark Adamson, wrote the following description of this
picture for me.  He did a great job so I am sharing it with the rest of
the group.

start with an all black screen, since it is the nightside of the planet.
point the camera at america, so you can see all of that continent plus the
upper half of the south american content. if there were light, you'd be
able to see alaska curving off in the upper left.
leave the shutter open so you get a heavy exposure, and develop the film
with a lot of contrast.  what do you get?   you see all the major cities
lit up by their lamp posts and light pollution. the entire american
territory is defined by thousands of points of light, each representing a
city. from boston down to new york and d c is one long stretch of bright
light. san diego, the bay area, and seattle are all long streaks too.
mexico has spotty light, and somewhere around el salvador or belize is a
bright city too. then into south america, the northern coast is all lit up
but most of columbia and equador are dark. the eastern horn of brazili is
well defined by lights too.  and lastly, the carribean islands are all lit
up as well.

if anyone is watching, they know where all the cities are, that's for
sure.

Blue skies.
Dan Rossi
Carnegie Mellon University.
E-Mail: [log in to unmask]
Tel:    (412) 268-9081
On Fri, 1 Feb 2002, Mary Blanton wrote:

> For all that can see it.  WAY TO GO NASA!!!  I KNEW something of my Tax
> Dollarhad to be spent on something worthwhile for me.
>
> http://antwrp.gsfc.nasa.gov/apod/image/0011/earthlights_dmsp_big.jpg
>
>
> VICUG-L is the Visually Impaired Computer User Group List.
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>

--
Blue skies.
Dan Rossi
Carnegie Mellon University.
E-Mail: [log in to unmask]
Tel:    (412) 268-9081


VICUG-L is the Visually Impaired Computer User Group List.
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[log in to unmask]  In the body of the message, simply type
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 VICUG-L is archived on the World Wide Web at
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