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Unmanned Spaceflight.com _ Cassini general discussion and science results _ Sun From Saturn?

Posted by: MizarKey Feb 27 2005, 06:12 AM

Could this be a shot of the Sun from Saturn, or just an unidentified moon?

Posted by: Bill Harris Feb 27 2005, 03:41 PM

Hmmm, might be. It seems way too bright to be a moon. This image is W00005099, which is the wide-angle camera. There are "solar system simulations" that will let you see where the Sun is from another planet. Otherwise, I'll dig out my star atlases and ephemeris and see if I can intuit where the Sun out ot be and match up the star field.

--Bill

Posted by: djellison Feb 27 2005, 06:32 PM

No way is that the sun. The exposure required to see the stars that well would have totally bleached out the CCD if it was pointing at the sun

probably just a highly over exposed moon

Doug

Posted by: TheChemist Feb 27 2005, 07:09 PM

Any idea why this object looks hexagonal ?

Posted by: Roby72 Feb 27 2005, 08:01 PM

I suspect it looks hexagonal because within the wide-angle objective, that took this image are some girders mounted (possible 3 in 120°). Thus light that passes through the optics diffracted in way that bright stars (or moons) looks hexagonal.

The WA of Cassini is mechanical a Voyager rebuilt (as I recall) and the Voyager optics has some test lamp mounted with help of girders inside the objective.
Hope this helps !

regards
Robert

Posted by: Bill Harris Feb 27 2005, 11:28 PM

Doug is right; I was engaging in wishful thinking. My mental image of the Sun from Saturn is a very, very bright star, but much too bright for that image.

I have a similar photo through and 8" telescope of Mars (or Jupiter) passing through the Beehive star cluster in '92 or '93. The bright planet showed diffraction spikes and was in a starry background.

--Bill