[ValleyNature] My Jupiter-Neptune Galileo Moment Observation

[Sherman Williams]

I had a very successful morning (May 27) focused on Jupiter and  
Neptune. The sky was mostly clear (a slight haze) but quite suitable  
for my early morning observation of Jupiter and Neptune. Certainly  
the best period for viewing was the half hour straddling 4 a.m.

I truly felt a connection with Galileo, as I studied the eyepiece  
star field, trying to evaluate the distances between objects in terms  
of Jupiter-half-diameters as Galileo had done for his diagrams of  
Jupiter with its moons.     or
<  http://articles.adsabs.harvard.edu//full/1997BaltA...6...97S/ 
0000099.000.html  >   I recorded my observations at the telescope in  
a diagram based on Jupiter-half-diameters units  (perhaps I'll have a  
chance to share the result later).

My main observations were made between 03:50, and 04:25 , but made a  
last one at 04:40, just before I put the scope away. I made the view  
through my 10X50 binoculars my first observation.    I found the  
binocular view a big challenge. The contrast of Jupiter's brightness  
made it really difficult to single out Neptune's dim light only a  
fraction of a degree away.  I really had to have the binoculars well  
focused and steady to keep Neptune in view. I had to find ways to  
diminish Jupiter's light by putting just out of the field o view to  
get a stronger image of Neptune, ....but see it, I did:  Jupiter  
below, Neptune, a faint little point  above-left ,  and the brighter  
star in the field,  mu Capricorni above-right.  Two planets and a  
star in the same view.    I would judge that some observers would  
have had some difficulty deciding whether or not they could see  
Neptune. If I had not known what I was looking for and what to expect  
I would have been in doubt.

  The view in my telescope was a different story. I used  46X and 92X  
with my 254mm Coulter (a 10 inch diameter reflecting telescope).    
The view of Neptune, Jupiter and Mu Capricorni were easily framed in  
the view (at those powers,  Neptune's disk eluded me, Roy Bishop  
reported being able to see Neptune's disk at ). Jupiter's disk and  
its 4 Galilean moons was a great sight (two moons were arranged on  
each side of the planet.  By  04:20 I had an initial sketch of the  
view made.  At 4:25 I could still see Neptune steadily,  but  
certainly the dawn was beginning to overwhelm the view of fainter  
points.   In my final look, just before 04:40, It was difficult to  
see Neptune's point of light; I could hold it in view only momentarily.

Toward the end of my observations I was aware of the growing dawn  
chorus of birds. About 4:30 a robin started its melody, to be joined  
by other robins and 2 or 3 Verry thrushes, along with song sparrows,  
an Oven Bird and crowing pheasants.    I also attempted a peek at  
Venus and Mars; Venus was there (low east) but Mars was covered in  
hazy, low cloud. I forgot about looking for Uranus until it was too  
late.  I didn't hear the owl Roy spoke of. but i did hear the beat of  
waves washing in on the beach below (the full tide would have just  
started to ebb (high at 03:30)). The whole experience made for a  
wonderful early morning. Dare I say that it felt like Galileo and I  
had just spent some time together?

Sherman
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