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Old August 20th 06, 08:43 PM posted to uk.sci.astronomy
David Randell
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Posts: 4
Default Interesting photo...

Nope, it is Jupiter, the band across the middle is at the correct angle.
Just a pity that the Jovian moons don't show. Callisto is close by at
the left hand side of the band.




I think you are mistaken here...

If you measure the image posted (ignoring any saturation of the pixels) the
estimated pixel-diameter proportion of the two images are in the region of
74:12, which would mean that what is being taken as an image of Jupiter's
disc subtends far too large an angle. Given the Moon subtends 30arcmins, at
this same scale the disc of Jupiter would subtend ~290arcsecs, or 6.5x too
large.

Then note the camera used, its a Canon A80 (which I have). At full zoom
(23.4mm) and full resolution, the image scale works out as 27.3arcsecs/px.
The disc of the full Moon at that image scale subtends ~66 pixels, and
Jupiter at 45arcsecs a mere two pixels! Yes you can image at least one of
the Galilean satellites with the A80 at full zoom (and I have done so), but
no way will you image the true disc of the planet at that focal length.

This is not to say the image is not an image of Jupiter, it may well be.
But if it is, it is not an image of the true disc of the planet imaged with
the A80 without additionally coupling it afocally to a telescope.

Dave Randell