NGC/IC Abbreviations

Note: The following is a transcription of J. L. E. Dreyer's description of the abbreviations and symbols, as used in the "Summary Description" column of the NGC, as taken from the original NGC. Every attempt has been made to retain the original formatting, where possible, of the text and symbols, as it was printed in the introductory section of the original NGC, as published in 1888. The two pages of the original NGC, which contain this information, have been electronically scanned, and are located here and here.

 
The "Summary Description" of objects not occuring in the General Catalogue
represents the observer's own words as nearly as possible, except that I
have always changed M. STEPHAN'S eeF into eF, and eF into vF, as such of
his novae which have been found independently by other observers have
always by these been described as somewhat brighter than by M. STEPHAN.
The system of abbreviated description used in the observations of the two
HERSCHELS has been in use so long that it is unneccessary to enter into a
lengthy explanation of it, except to call attention to the progressive
scale of brightness, size, and form adopted by Sir JOHN HERSCHEL.

      1. excessively faint     excessively small, 3" to 4" diam.
      2. very faint            very small, 10" to 12" diam.
      3. faint                 small, 20" to 30" diam.
      4. considerably faint    considerably small, 20" to 30" diam.
      5. pretty faint          pretty small, 50" to 60" diam.
      6. pretty bright         pretty large, 50" to 60" diam.
      7. considerably bright   considerably large, 3' to 4' diam.
      8. bright                large, 3' to 4' diam.
      9. very bright           very large, 8' to 10' diam.
     10. excessively bright    excessively large, 20' and upwards.*

* In estimating clusters of well-separated and scattered stars a wider
acceptation must be understood, so that, e.g., a cluster of 1' in extent
would be very small, and one of 15' or 20' large.

In the case of form, the scale was supposed arranged in the order:
round, very little extended, elliptic or oval, considerably extended,
pretty much extended, much extended, very much extended, extremely
extended.

The following is a complete list of the abbreviations:-

Ab..............about                 n..............north 
alm.............almost                neb............nebula 
am..............among                 nf.............north following 
app.............appended              np.............north preceding 
att.............attached              nr.............near 
b...............brighter              N..............Nucleus, or to a
                                                     Nucleus 
be..............between               p..............pretty (before
                                                     F,B,L,S) 
biN.............binuclear             p..............preceding 
bn..............brightest towards     pg.............pretty gradually 
                the north side        pm.............pretty much 
bs..............brightest towards     ps.............pretty suddenly 
                the south side        P..............poor 
bp..............brightest towards     quad...........quadrilateral 
                the preceding side    quar...........quartile 
bf..............brightest towards     r..............resolvable 
                the following side                   (mottled,not resolved) 
B...............bright                rr.............partially relolved,
c...............considerably                         some stars seen 
ch..............chevelure             rrr............well resolved, clearly
co..............coarse, coarsely                     consisting of stars 
com.............cometic               R..............round 
cont............in contact            RR.............exactly round 
C...............compressed            Ri.............rich 
C.G.H...........Cape of Good Hope     s..............suddenly 
Cl..............cluster               s..............south 
d...............diameter              sp.............south preceding 
def.............defined               sf.............south following 
dif.............diffused              sc.............scattered 
diffic..........difficult             st.............stars 
dist............distance or           sev............several 
                distant               susp...........suspected 
D...............double                sh.............shaped 
e...............extremely,            stell..........stellar 
                excessively           S..............small 
ee..............most extremely        sm.............smaller 
er..............easily resolvable     triN...........trinuclear 
exc.............excentric             trap...........trapezium 
E...............extended              v..............very 
f...............following             vv.............very, very 
F...............faint                 var............variable 
g...............gradually             *..............a star: *10, a star of
gr..............group                                10th magnitude 
i...............irregular             **.............double star 
inv.............involved,involving    ***............triple star 
iF..............irregular figure      !..............remarkable 
l...............little,long           !!.............very remarkable 
L...............large                 !!!............a magnificent or 
m...............much                                 otherwise interesting 
mm..............mixed magnitudes                     object 
mn..............milky nebulosity      st 9 .........stars from the 9th 
M...............middle, or in the                    magnitude downwards 
                middle                st 913 .......stars from the 9th
                                                     to 13th magnitude

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