Re: Epsilon Lyrae separation and optics

Brian Tung wrote: 
Brian Murphy wrote:

I've read that here on SAA before and I question it. If the moons could
be resolved naked eye, why wasn't it widely reported before Galileo?


Because they weren't expecting to see it.  Galileo recorded Neptune
in Jupiter's background.  Several people recorded Uranus before its
discovery.  Even Herschel thought at first that he had discovered a
comet.  I suspect this is in large part because these folks expected
there to be six planets, so that's how many there were.

I think something similar applies to Jupiter's satellites.  No one
before Galileo had ever suspected that Jupiter had satellites, and so
no one ever mentioned any.  Even if they had seen one, they would
likely have just thought that it was a background star or an optical
illusion.

I exepct they would just assume it was a background star. And most times it is. The bright planets get close to faint naked eye visible stars fairly often and they would have to spot that one of them was moving with Jupiter. Without accurate star maps this seems unlikely.

It does seem to the be case that is mostly childern that can see it, so there is also the possibility that they saw it and were not believed.

Your mention of the historical Chinese observational reference is interesting. Any references beyond the book?

Regards,
Martin Brown
.

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