Darker areas in the oceans, why? Earth Night Picture 1Oct'06
Darker areas in the oceans, why? Earth Night Picture 1Oct'06
Do the lighter parts indicate luminous life forms, and the darker a lack of same? Is it related to clouds on the day the picture for each section was taken?
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The question refers to the 2006 Oct 1 Night Picture of Earth, http://antwrp.gsfc.nasa.gov/apod/ap061001.html. It seems that the images may contain unexpected information about the oceans encoded in the difference in brightness.
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ohhhhhhh you mean this image'
http://antwrp.gsfc.nasa.gov/apod/ap061001.html
And I thought the reference was to a Night Sky Live image. Being posted in that part of the forum. Thanks for moving it to APOD Nereid.
Dcpattis may have a point about more information in the images. Many times discoveries are made years later by someone noticing things over looked by previous researchers.
Norval
http://antwrp.gsfc.nasa.gov/apod/ap061001.html
And I thought the reference was to a Night Sky Live image. Being posted in that part of the forum. Thanks for moving it to APOD Nereid.
Dcpattis may have a point about more information in the images. Many times discoveries are made years later by someone noticing things over looked by previous researchers.
Norval
"It's not what you know, or don't know, but what you know that isn't so that will hurt you." Will Rodgers 1938
Could it have to do with the optical density of the oceans? The oceans had a certain brightness, but when it was stretched out to fit that particular earth-projection, that particular part got darker?
Or maybe some of the light of the oceans is actually reflections from the light of the moon, in which case the poles would get less just like they get less of the sun's light.
Or maybe the different coldness of the water affects the density of the water, which changes its albedo (ability to reflect light).
Maybe it has to do with wind/water currents or depths that change the relative shape of the wave in different locations, altering how it reflects light.
Can't say for sure, but these are my guesses. Maybe it'll spark someone to come up with a more complete answer.
Or maybe some of the light of the oceans is actually reflections from the light of the moon, in which case the poles would get less just like they get less of the sun's light.
Or maybe the different coldness of the water affects the density of the water, which changes its albedo (ability to reflect light).
Maybe it has to do with wind/water currents or depths that change the relative shape of the wave in different locations, altering how it reflects light.
Can't say for sure, but these are my guesses. Maybe it'll spark someone to come up with a more complete answer.
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moonlight
The actual reason might not be IR at all. Note that the spacecraft in use were meant to get good images using moonlight. Any person who has done astrophotography knows that with a little time exposure or wide aperture work, you can get excellent images using nothing more than moonlight.
I would suspect that what we are seeing is plankton or krill coloring the warmer waters and showing up faintly in that moonlight.
I would suspect that what we are seeing is plankton or krill coloring the warmer waters and showing up faintly in that moonlight.
Cheers!
Sir Charles W. Shults III
Sir Charles W. Shults III
Well,
Mr Simmon returned the answer:
Because it's fake! The background of the night lights image is a darkened and tinted version of a daylight composite image in which the color of the oceans corresponded to depth. I created a newer version where the ocean of the ocean is related to phytoplankton concentration, but the effect is small:
http://visibleearth.nasa.gov/view_rec.php?id=1438
He is right about the link being different
Mr Simmon returned the answer:
Because it's fake! The background of the night lights image is a darkened and tinted version of a daylight composite image in which the color of the oceans corresponded to depth. I created a newer version where the ocean of the ocean is related to phytoplankton concentration, but the effect is small:
http://visibleearth.nasa.gov/view_rec.php?id=1438
He is right about the link being different
I believe that the image links under "Images and animations" are the new image talked about. They do loose the reference to continents and seem to show only light concentrations. Mr Simmon did state that some things were lost and others didn't show well.
http://veimages.gsfc.nasa.gov/1438/earth_lights.gif
http://veimages.gsfc.nasa.gov/1438/earth_lights.gif