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Re: (IAAC) Obj: NGC 40 - Inst: Celestron 8"



>But what do [snip - see below] mean??   Nick
I'm glad you asked that, Nick! ;>
Here's a brief rundown of "NGC notation", as *I* understand it: others please 
correct me where I stray! (Jeff M. - open invitation ;>>)
Ga Lo 120.02  Ga La 9.87  Galactic Latitude and Longitude coordinates:
                          The Milky Way's central axis is the galactic
                          "equator", and Sag A is the "prime merdian".
POSS X 150  POSS Y 160    Palomar Observatory Sky Survey coordinates.
Old F,VS,R,VSMBM,*12SP    Object descr. from original New General Cat.
New                       Description from the Revised NGC catalog.
Xrf P                     No idea! Maybe other catalogs with this obj?
The two "Old" and "New" object-description fields have their own well-defined 
notation... Some of the standard abbreviations I know are:
F	faint		B	bright		R	round
S	small		L	large		E	elongated
v,V	very		p,P	pretty		s,S	suddenly
m,M	much		vl,VL	very little	g,G	gradually
BM	brighter toward the middle	c,C	considerably
HISB	high surface brightness		DIF	diffuse
DKLNS   showing dark lanes		*INV	star(s) involved
So "VSMBM" is "very suddenly much brighter to the middle" (in other words, 
"well concentrated to a bright core"). The whole description above might be 
"faint, small, round, well concentrated to bright core, mag 12 star visible 
South Preceding the object..."
Keep in mind that these are NOT amateur visual descriptions: I believe they 
usually derive from various photographic surveys this Century and last... 
Probably for that reason, I rarely find them useful for my observing.
Clear skies!
Lew

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