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Ngc2175 Monkey Head neb & Ngc7789 Open Cluster

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#1 DavidC



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Posted 02 February 2013 - 04:40 PM

The other night I looked in vain for Ngc2175 the Monkey Head nebula in the outskirts of Orion, in the same area as M35, and also Ngc7789 an Open Cluster in Cassiopeia. I was told that 7789 has the surface area about as large as the Moon, but even using a 26mm Ep, it seemed to be elusive. Is the Monkey Head going to show up as a dark patch? I'm in an Orange zone, so I'm sure Lp is a factor for the Monkey, but I wouldn't think that would affect an OC much. I can see M35 and M37 clearly on most nights. Maybe I just need to go to darker skies, huh.
Thanks, David

#2 Jon Isaacs

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Posted 02 February 2013 - 04:49 PM

To see the nebulosity in region of NGC2175 takes reasonably dark skies and I find a O-III filter or Ultrablock filter helps significantly. I stumbled upon it a year or two back from my site where the skies are classed as "blue." I doubt it would be visible from an orange zone though with the right filter it might be detected.

What scope are you using?


#3 GlennLeDrew


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Posted 02 February 2013 - 04:53 PM

Darker skies always help.

From your orange zone you should see the nebula when using a nebula filter. Stay at a fairly low power, as the nebula is fairly large, and some surrounding sky to better frame it will aid in detection.

You have sufficient aperture to see many stars in the cluster, which should become visible at moderate to moderately high magnification.

From a dark site, where stars to 6th magnitude are seen by the eye alone, both these objects are well enough visible as hazy spots in (unfiltered) 7X35 binoculars.

#4 John Kuraoka

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Posted 02 February 2013 - 05:46 PM

From my front yard, 7789 in my scope looks pretty scattered and I can't make out any distinct cloud of light, so it might be easy to pass by. Once I find it, though, I like looking for the different colored stars within it. Even bucking the neighbor's porch lights, it's fairly easy to spot in a pair of 7x35 binoculars.

#5 DavidC



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Posted 02 February 2013 - 06:14 PM

Thanks for the replies, I'm going out again on Monday night. I didn't think I would see the Monkey head very easy, I wonder if a LP filter might help, that's all I've got right now. The OC I would think would be a little easier, I hear its large in area.
Thanks, David

#6 Jim Nelson

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Posted 02 February 2013 - 09:01 PM

NGC7789 is perhaps my favorite open cluster. It's large and it's total integrated brightness is pretty high...but it can be more elusive than you think. It's very rich for such a large cluster, but the numerous stars all appear quite uniformly faint. I find it fascinating to look at.

If you're looking for something that looks like either m35 or m37, you could easily miss it in brightish skies. From bright skies in a small scope at low power, it can appear as a terribly ghostly faint glow, that with higher power will break up into a grainy glow something like a globular cluster without a central condensation. Darker skies and moderate to large apertures will really "let it shine", although it will always be more subtle than M35 and M37.

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