I had a chance to observe this globular cluster last night in very good seeing and transparency.
My sense of the scene was a bright very condensed central spot surrounded by a halo of light that was brighter closer to the central spot. So, yes, it certainly appeared just as you had described. I spent a while observing trying to check that I was not being misled to simply seeing what you had reported.
At one point I hopped over to NGC 2808 in Carina to compare observations. Here, there is a quite broad bright central core and a surrounding spray of light, much of which, shows resolved pin point stars and the rest looks right on the edge of resolving into individual stars. This did not look mist like.
It was an interesting target. I too, shall be interested to hear of others observations.
Scope: Vixen NA140SS on TRex mount and Pan24, LVW 13 & 8 eyepieces.
Quote:
Originally Posted by Tropo-Bob
I have long been intrigued with this globular. I first observed it in 1981 with my 8" F7 reflector and made the note: "It's like a dull, torchlight pointed at me, but shining through a mist."
I had the same impression when I observed it many years later with my 12" F5 Dob. I observed it 3 nights ago with my new Tak 100D (F7.4) and still saw that effect with the lessor aperture.
In the Stephen James O'Meara Calwell Objects (P 291), Stephen says that ; "The overall impression is that of the great Hercules globular M13 seen through a fog." NGC 1851 is also known at Caldwell 73.
I have seen this 'fog/mist' affect only on this globular. I am interested if others see it? Strangely, Hershel saw it, but only with his right eye; not his left eye! (Ibid P288).
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