Archive for October 2015

NGC 7128 – Open Cluster – Cygnus

October 24, 2015

Pencil sketch using a 10-inch Newtonian reflector @ 190x.  Roger IvesterFullSizeRender

Pencil sketch:  Inverted color 

Rogers NGC-7128a

Observer’s Challenge Link:

OCTOBER 2015 OBSERVERS CHALLENGE – NGC-7128

NGC 7128 – Open Cluster in Cygnus –  
Date: October 2015
Conditions: Very Good
NELM: 5.2
Telescope: 10-Inch Newtonian reflector
Eyepiece: 12 mm + 2x Barlow
Magnification: 190x
FOV: 0.32º – 19 arc minutes

Easy to locate and see at low magnification, appearing as a small concentrated round hazy spot, with several bright stars on the outer edges. When increasing the magnification to 190x about 13 stars could be counted encircling a hazy central region of fainter stars. At the higher magnification the cluster became octagonal in shape. I could count three pair of doubles in the outer ring. The brightest star is magnitude 11 on the SSE tip. The cluster was much smaller than I remembered when I observed it last on 9-27-93, using the same telescope and from the same site.

The late North Carolina amateur, Tom Lorenzin said: “small compressed and memorable! brighter members make a small pentagon.”    Roger Ivester

The following pencil sketch was made by Jaakko Saloranto of Finland, using a 4.5-inch Newtonian reflector @ 261x with a NELM of around 6.0. 

“Small 2.5′ cluster of ~10 stars magnitudes 11-13. Easily visible @ 38x (66′) as a small glow NW of 10th magnitude star. Sky conditions and weather: 20°F, humidity 84%, Aurora Borealis in the northern sky. SQM-L reading 20.05 aimed at the object with naked eye limiting magnitude around 6.0.”  

NGC7128

The following image was made by Dr. James Dire from Hawaii, using a 10-inch F/6 Newtonian Reflector and a SBIC ST-2000XCM CCD Camera.  Exposure 30 minutes… 

NGC7128

NGC 7000 “The North America Nebula” Cygnus

October 13, 2015

 Las Vegas Astronomical Society Observer’s Challenge link: 

SEPTEMBER 2015 OBSERVERS CHALLENGE – NGC-7000-1

The following pencil sketch was made using a blank 5 x 8 notecard with a 10-inch Newtonian reflector telescope.  The observation, notes and sketch were made from my moderately light polluted backyard, located in the Foothills of North Carolina.    roger ivester

Scanned Image 160930002

 

NGC 7000 “The North America Nebula” Cygnus
Date: September 17, 2015
Conditions: Fair seeing with a NELM of 5.0

Telescope: 10-inch f/4.5 Newtonian Reflector
Sketch: 36x with an O-III Filter
FOV: 1.8º

A dark sky is preferred for this very large emission nebula, however, I’ve observed the North American to a satisfactory level on many occasions from my moderately light polluted backyard using my 10-inch reflector. An O-lll filter is essential when observing this object.

Covering my head with a commercial black astro-cloth to shield ambient light from entering my eye, was very beneficial.  The difference was amazing, as the outline of the nebula became much sharper and brighter with the covering.  

The dark region known as “the Gulf of Mexico” is the most noticeable feature. At 36x and with a FOV of 1.8º, much of the North American shape was visible.

Open star cluster, NGC 6997, a sprinkling of faint stars is located in the “Ohio” region. If using an O-III or UHC filter while observing the North American Nebula, be sure to remove when observing this cluster.

IC 5070, “The Pelican Nebula” lies just to the west of NGC 7000. The Pelican was fairly easy to see, appearing as a large very faint diffuse region without any definitive shape.   Roger Ivester

The following wide field image by Dr. James Dire of Hawaii using a Canon 30D camera with a 100 mm f/2 lens.  Exposure 30 minutes piggyback on a telescope.     

Dire image 1