Observing Omega Centauri And Centaurus A From North Carolina At +35º North Latitude

After years of wondering if I could see globular cluster (NGC 5139) Omega Centauri and galaxy (NGC 5128) Centaurus A from my home at a latitude of +35º 18′ so I gave it a try on April 26th 2009.  

My poor southern view required that I go to a dark-site on the southern rim of the South Mountains, only thirty minutes away.  I also met two other local amateurs at the site, with one bringing a 12-inch Newtonian, which was invaluable in seeing galaxy Centaurus A. The 12-inch also provided an excellent resolve of Omega Centauri, despite the telescope being almost parallel to the ground. 

Theoretical limiting horizon calculation from Western North Carolina at +35º North Latitude:

(90º-35º) = -55º theoretical limiting South Latitude. 

Omega Centauri South Latitude:  -47º 28′  

My limiting southern horizon @ -55º (-) -47º = Only 8º above my theoretical southern horizon, and again…which puts my telescope tube almost parallel to the ground!   I share the following of that night:

I made the following sketch on 4-26-09, using a 102mm f/10 refractor. The NELM was ~6.5 at the zenith and with a good view of the southern horizon. However, the excellent seeing overhead did not transfer to the extremely low southern view as expected, at only 8º’s about my limiting horizon. 

The sketch of Omega Centauri with the 102mm was made “during the observation” at the eyepiece, at a magnification of 42x, using a white charcoal pencil on black card stock. The globular appeared fairly dim, mostly round, well-defined edges, granular with some brighter members sparkling in the interior with averted vision.  I also noted many faint outliers enveloping the cluster. When observing with the 12-inch f/5 reflector, the cluster was “surprisingly” well resolved. 

Observing Centaurus A using a 12-inch Newtonian:

Despite observing at a dark-site, I was looking over many distant lights, and many layers of atmosphere which diminished the view significantly.  I “could not” see the galaxy with my 102mm refractor.

Observing Centaurus A with the 12-inch f/5 reflector…it was extremely difficult.  My notes read: Difficult! Appearing only as a small smudge with a stellar nucleus.  Regardless, of the poor view of Centaurus A, I was very happy to have been able to observe and sketch Omega Centauri and at least to be able to see Centaurus A from the foothills of North Carolina.  

Rough Field-Sketch as following made on 4-26-09 @ 1:00 AM EDT

Rough field sketch with 12-inch f/5 Newtonian from the same location and night:

James Dire Image from Barking Sands, Kauai, Hawaii

Stellarview 102mm f/6.3 refractor w/Teleview 0.8x focal reducer flattener

James Dire: 100mm Lens Canon DSLR Camera

Omega Centauri reports:

Fred Rayworth of Las Vegas, saw Omega Centauri from Cathedral Gorge, Utah @ +37º 49′ 20″

“I saw Omega Centauri just over the hood of a truck on the horizon. I had a chance to see it at Death Valley, California when we went to the airport, but never caught it.”

+90º North (-) +37º 50′ = (-) 52º 50 mins or limiting southern horizon

So:  -52º 50′ (-) -47º 28′ = ~ 5º 22 mins above the horizon from Cathedral Gorge.    

Larry McHenry: Observing from West Virginia

Globular cluster NGC 5139 – Omega Centauri

Location: Calhoun County Park in central West Virginia. Setup on a ridge of about 1100 ft in elevation. (more about Calhoun at: http://stellar-journ…calhounpark.htm 

At the time of observation, NGC 5139 had an elevation of about 3.5º

First a wide-field “finder” image of NGC 5139 (Omega Centauri) using my Canon 100mm video lens & ASI290MC camera. 

Here’s the main EAA observation of Omega Centauri, again thru the trees, from 4/28/22 at 12:28 AM.

(8-inch SCT @ f/6.3 on an Atlas German equatorial mount , ZWO ASI294MC camera with L-Pro filter, 20 second subs, no dark or flat frames, not guided, live-stacked using Sharpcap for 80 seconds). 

Due to the short exposure time, we were able to see the dark feature called the “Eye of Omega”, which is possibly a dark molecular cloud that is in front of the cluster in our line-of-sight. 
This is generally only seen visually, as most images are longer exposures to pull-out more of the cluster stars. 

The timing was really good for making this observation thru the trees, as the foliage was noticeably thicker a few days later as warm weather really brought on the leaves.

And an observation of galaxy NGC5128 – “Centaurus A” made about 20 minutes prior to the hunt for Omega. (same location as above)

With a higher elevation of 8 degrees, I was able to catch the galaxy sailing thru a clear gap between trees, before it too eventually dived back into the limbs.

(8-inch SCT @ f/6.3, ZWO ASI294MC camera with L-Pro filter, 3 minute subs, dark & flat calibration frames, PHD guided, live-stacked using Sharpcap for 15 minutes).

Overall, It was a successful observing trip!


The park is opening a new observing field on a different ridge that has clear sight-lines to the horizon (one ridge over). Omega should be “in the clear” from there!

Unfortunately, I’ll be at the Cherry Springs Star Party for the next New Moon, and my club’s observatory (ORAS) for June. Next trip to Calhoun wont be until July, so a better observation of Omega will have to wait for one more year.

Larry McHenry

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