In the description of this image it is claimed that Moon should be detectable in famous "Pale Blue Dot" image.

Detailed analysis also suggests that Voyager detected the moon as well, but it is too faint to be seen without special processing.


And recently NASA released reprocessed version of it by Kevin M. Gill to bring out the details using latest image processing techniques. https://photojournal.jpl.nasa.gov/catalog/PIA23645

But there isn't any mention of Moon or where it should be in the image with respect to Earth so I was hoping someone can work out where Moon is supposed to be, perhaps image processing masters have coaxed it out unknowingly and we are just not paying attention!

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    $\begingroup$ I heard Carl Sagan on TV saying "the Earth was even less than a single pixel". So there would be only two pixels separated by a few dark pixels. $\endgroup$ – Uwe Feb 13 at 21:50
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    $\begingroup$ "Earth was a crescent only 0.12 pixel in size". This would mean the moon should be (384000/6371)*0.12 ~ 7.2 pixels from the earth. Suffice to say, I haven't found anything like that in either image, but I didn't get to look at the raw data. $\endgroup$ – Polygnome Feb 14 at 8:48
  • $\begingroup$ Moons diameter is only 0.2727 of the Earths diameter, so Moon was only 0.032 pixel in size. Was the camera able to detect such a tiny and dark spot? $\endgroup$ – Uwe Feb 14 at 12:11
  • $\begingroup$ My WAG (wild -A -guess) is that the "special processing" involves many images over time & a data-fitting analysis done to find positional perturbations or occultations. Similar to our indirect detection of planets around other stars. $\endgroup$ – Carl Witthoft Feb 14 at 13:14
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    $\begingroup$ @Uwe what you forget is that the object size , for all objects less than a pixel, is irrelevant. The camera pixel limits resolution, but it's the object's brightness vs. the camera SNR which determines whether that pixel goes "bright" $\endgroup$ – Carl Witthoft Feb 14 at 13:16

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