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Old 12-May-2008, 05:39 AM
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tiff_seattle tiff_seattle is offline
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Default question about the "pale blue dot"

In the "Pale Blue Dot" image taken by Voyager 1, we see the Earth in what is described as "a beam of scattered sunlight". Can someone explain to me what is happening here, and why the beam of light appears in the photograph? Shouldn't the light be radiating in all directions equally from the Sun? Is this just some artifact due to the location of Voyager when this picture was taken? I have searched online, but have not been able to find an explanation for this.
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Old 12-May-2008, 12:56 PM
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Quote:
Originally Posted by tiff_seattle View Post
In the "Pale Blue Dot" image taken by Voyager 1, we see the Earth in what is described as "a beam of scattered sunlight".
I think someone was a bit too poetic with that caption.

Planetary Society: Pale Blue Dot Poster

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The apparent rays of light are not sunbeams, but scattering off the camera's optics, a result of pointing it so close to the Sun.
Planetary Photojournal: PIA02228: Solar System Portrait - Earth

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This image the Earth is a mere point of light, a crescent only 0.12 pixel in size. Our planet was caught in the center of one of the scattered light rays resulting from taking the image so close to the sun.
Similar at Planetary Photojournal: PIA00452: Solar System Portrait - Earth as 'Pale Blue Dot'

And, welcome to BAUT Forum, tiff_seattle.
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Old 12-May-2008, 02:22 PM
BISMARCK BISMARCK is offline
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I have a question: I've never understood how part of a digital image can be "smaller than a pixel".

Aren't pixels by definition the smallest unit of a digital image?
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Old 12-May-2008, 03:33 PM
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I have a question: I've never understood how part of a digital image can be "smaller than a pixel".
You can know the area earth covers at that distance. You can know the area a pixel covers at the distance of earth. You can divide one by the other.
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Old 12-May-2008, 04:26 PM
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Quote:
Originally Posted by BISMARCK View Post
I have a question: I've never understood how part of a digital image can be "smaller than a pixel".

Aren't pixels by definition the smallest unit of a digital image?
Apparently, the color of the Earth only contributed an eighth to the color of that particular pixel.
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