Thread: Stupid Question
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Old June 9th 04, 09:16 AM
Martin Brown
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Default Stupid Question

In message , Brian Tung writes
Steve wrote:
When I see these images of planets within our solar system, why do I
never see stars in the backdrop (at least that I can remember?)


Generally speaking, the planet is too bright for an exposure long enough
to capture any stars in addition.


Or you can burn out the planetary disk and see satellites (for Jupiter
and outwards) and any bright field stars. Actually with modern astro-CCD
imaging if you stretch the contrast on a decent image you can usually
see the Jovian satellites and the belt detail on a single exposure.

On the rare occasions when the moon passes between us and a planet you
get to see the difference in brightness and size clearly. The last time
Saturn passed behind a gibbous phase moon was very pretty indeed.

It is quite rare to get a bright star and a planet in close proximity.

Regards,
--
Martin Brown