[Lvas] M-13, the propeller, and scope review

[roger ivester]

All,

 

Steve Davis and I easily saw the propeller last night using Steve's 12-inch Meade Lightbridge. We observed from the base of the South Mountains, only 20 minutes north of my home in Boiling Springs, North Carolina. The temperature was a comfortable 50° with slightly breezy conditions. Limiting naked eye magnitude would easily exceed 6.5. Both of us rated the seeing as good, but not excellent. We observed till after midnight.   

 

Steve saw it immediately at almost two hours from the meridian. Using a 7mm Nagler @ 196x. The cluster presented itself as a very large, well resolved cluster with many star chains and dark crevices throughout. A Meade Plossl seemed to work just as well or maybe better as we could see fainter stars within the cluster, with possibly better contrast, especially at the edges of the cluster. This being due in part to the elimination of the extra lenses. We both agreed on this, and Steve has all of the Naglers. 

  

I found that I could better see the propeller using averted vision. During each scan with my eyes, a different dark lane would stand out....a most interesting phenomenon. 

 

Both of us were surprised that we had never seen the dark lanes before. 

 

I must also say that I have never been more impressed with any telescope than Steve's 12-Meade Lightbridge. My adjustable observing chair would place my head and eyes in perfect position for a sketch. The movements of the mount was "silky" smooth. I really like the portability of this scope. It is my opinion that this is the perfect balance between mirror size and ease of use...for almost anyone. I may consider one of these scopes in the future. Definitely a scope that is easy on your back.   

 

The mirror was "textbook". Diffraction rings were almost identical on each side of focus. At high power the airy disk was one faint ring surrounding the star. I was pretty amazed with the optics, especially considering the fast focal ratio. 

 

Both Steve and I will submit our "mostly" joint detailed notes of M-13 at a latter date to be used in June edition of the "observers challenge". 

 

Roger

 

 

  
 
 
    I can see how it might be possible for a man to look down upon the earth and be an atheist, but I cannot conceive how he could look up into the heavens and say there is no God.      Abraham Lincoln




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