[Lvas] Observer's Challenge For June

[roger ivester]

LVAS all,

 

Would it be acceptable to all, if we would make a change in our challenge for June?  

 

I had suggested adding the very faint galaxies N-4284 and N-4290. With our primary focus on M-13 and the propeller, it might be too much of a distraction. 

 

What about devoting all of our time to M-13 alone? We can spend a great deal of time working on this object...much more than yep, there it is. Hopefully, we will have a variety of scopes, and we will consider resolution, star chains, and of course, the dark lanes.      

 

We will think about NGC-4284 and 4290 next spring as our challenge objects, if agreeable with all...at that time. 

 

Please review Frank Barretts www.celestialwonders.com M-13 images and easily see the dark lanes.  
 
Our "Observers Challenge" for June will be M-13. We will be looking for the illusive "propeller" within M-13. Three dark lanes radiating from the central region. 

 
WSH brought presented this challenge in "Deep-Sky Wonder's" in Sky & Telescope, July 1953. 
 
In 1980 John Bortle saw the lanes with his 12.5-inch reflector at 176x. Dennis di Cicco at Stellafane in 1981 was surprised by how easily the lanes were seen with the 12-inch f/17 Porter turret telescope at about 180x. However, even knowing their orientation and appearance, he was unable to see them at 95x with a 12-inch that was set up nearby. Sighting the lanes seems to depend upon a careful balance of aperture and magnification. 
Both Bortle and Dennis di Cicco commented on the importance of magnification. Most observers note that they appear best at a magnification of about 200x. Information from "Deep-Sky Wonders" by Walter Scott Houston, selections and commentary by Stephen James O'Meara; Sky Publishing Corporation Cambridge, Massachusetts 1999.  

 

 
  


 

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