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Old 23-February-2006, 03:48 AM
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01101001 01101001 is offline
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Quote:
Originally Posted by TheBlackCat
The book says this is because it is too dark for the color-sensetive cones to operate and the rods that are still operating cannot differentiate color.
Do you not use averted vision to view dim stars?

Wikipedia: Eye

Quote:
Its requirement for high intensity light does cause problems for astronomers, as they cannot see dim stars, or other objects, using central vision because the light from these is not enough to stimulate cone cells. Because cone cells are all that exist directly in the fovea, astronomers have to look at stars through the "corner of their eyes" (averted vision) where rods also exist, and where the light is sufficient to stimulate cells, allowing the individual to observe distant stars.
What does the passage in question say, anyway? (I don't own a copy. I'm a bad person.) Does it say color cannot be seen for any stars or for most stars? I think I can tell the difference in bright stars, say Sirius's blue versus Betelgeuse's red, so I'd be surprised if the passage addressed all stars.
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Last edited by 01101001; 23-February-2006 at 05:53 PM.
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