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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
References: