Archive for November 2013

NGC 3893 Galaxy in Ursa Major and Faint Companion NGC 3896 – Seeing The Unseen

November 30, 2013

I wanted to share an article concerning an observation I made on April 20, 1993.  It’s a testament that documenting and taking good notes is indeed a good thing!   

During some recent cloudy weather, while reviewing past logbook entries, I discovered that I had not followed up on an object viewed on 20 April 1993.  The main object was NGC 3893, an 11th magnitude galaxy in Ursa Major.  While making my sketch of this excellent galaxy, I noticed a smaller, very faint object, SE and very close.  I noted this in my logbook as one to look up later.  But it was almost ten months later, while browsing through the logbook, that I remembered to follow up on this observation.

I checked Burnham’s Celestial Handbook, Tom Lorenzen’s 1000+, and the Tirion Sky Atlas 2000.0 only to find that none of these sources listed a companion galaxy.  I then went to the NGC-2000.0 Catalog by Roger Sinott, and found the companion listed as NGC 3896, a 14th magnitude galaxy. I was elated, as this was the faintest galaxy I had ever observed with my 10-inch reflector from my moderately light polluted backyard.  It should also be noted that this observation was made from my sun deck, with unshielded streetlights nearby. 

If I had not sketched NGC 3893, it is possible that I would have missed NGC 3896.  And, if I had not logged the companion, I probably would never have checked any reference material.  So, the moral of this story is:  Keep a logbook, sketch your observations, and periodically review your logbook.  You never know what you may find.

The following is the “rough” but original sketch made at the telescope eyepiece, without any alterations or changes.  After 20 years, I’m already excited about going back to NGC 3893 and NGC 3896…hopefully from a dark site.  I wonder how the fainter companion will present itself this time?  Hopefully, I will be able to produce a better sketch and improve my notes.  Please note:  The following sketch of both NGC 3893 and NGC 3896 is much brighter than the actual visual view.  

Roger

2014-04-08- 001

NGC 3893 and 3896 - Ursa Major -1

Advertisements

The Cocoon Nebula Notes and Sketch – IC 5146 – Cygnus

November 15, 2013

The Cocoon Nebula has been a difficult object for me.  I’ve tried many times over the years, but without success.  My location has always been from my moderately light polluted backyard, using a 10-inch reflector.  On the night of November 8th 2013, I was finally able to see the nebula and make the following sketch.   I used a magnification of 114x, however, the nebulosity would catch my eye a bit easier when using 57x.  A UHC filter was essential to see this faint and difficult object.  

To read the entire Observers Challenge, please click on the following link: OCTOBER 2013 OBSERVERS CHALLENGE – IC-5146

IC 5146 - Cocoon Nebula

NGC 7044 Sketch and Notes – Open Cluster In Cygnus

November 8, 2013

My first observation of NGC 7044 came in September 1994. I was very surprised how difficult this cluster was to locate and see. The 5.2 magnitude is very deceptive to say the least. I was using a 10-inch reflector and observing from my moderately light polluted backyard in the foothills of western North Carolina.  This cluster proved to be very difficult indeed.  I continued to check my star chart to insure that I was looking at the correct location.  The cluster finally came into view at a magnification of 114x.  When increasing the magnification to 250x, I was able to see a faint sparkling of very faint stars, with direct vision, but not constantly, and averted vision presented the best view.  The cluster appeared as a sprinkling of tiny diamonds in the bottom of a velvet bag…surprisingly beautiful!    

I noted five or more brighter stars superimposed over the fainter members…possibly foreground stars?  A pair of faint unequal stars are located on the NE edge of the cluster.

During the months of September and October 2013, I made over five observations from different locations and under varying conditions.  Using the same 10-inch reflector as 1994, this cluster seemed almost invisible, even from a dark site.  During moments of steady sky, at a magnification of 208x, a sudden sprinkling of very faint stars appeared, but again, not constant.   

It should be noted that during two of my most recent observing sessions, with an average naked-eye limiting magnitude of about 5.2, the cluster could not be seen.   

The following sketch was made using a No. 2 pencil, and a blank 5 x 8 note card, with the colors being inverted using a scanner.  Please note:  The sketch presents the cluster quite a bit brighter than could be seen visually.  

NGC 7044 OC Cygnus