Catalogue of Galaxy Groups

Wolfgang Steinicke

KDG 1 = NGC 23 (right) and NGC 26 (left)

Freiburg 1984 / 1999


Preface to the 1984 Edition

The Catalogue of Galaxy Groups (KDG) contains all pairs and groups of galaxies north of -20 declination with a limiting magnitude of 14.0m and a maximum distance of 15' for pairs. The 215 groups of the catalogue contain a total of 418 galaxies. These are, together with other interesting objects nearby, shown in the illustration part (see printed version). For every object all available data are presented.


Preface to the 1999 Edition

Definition and structure of the 1984 catalogue were not altered. The appendix contains a list of all groups, in which the data are updated (click below). All positions are measured with a precision of 1-2". It shows, that some new magnitudes are below 14m now. In 1984 for some pairs a total magnitude was given, e.g. NGC 4410A/B (KDG 136) with 13.6m, which is now splitted into 13.8m and 14.9. Nevertheless, for most entries the criteria are still valid. Two objects had to be renamed: KDG 28: NGC 930 is now NGC 932 (NGC 930 is a star) and KDG 117: NGC 4170 is now NGC 4173 (NGC 4170 is a star). Anyway, to keep the form, no group was rejected.

Catalogue of Galaxy Groups (ASCII-Daten)

Most of the data come from the Revised New General and Index Catalogue (Steinicke 2000). Here one can also finf the explanations to the abbreviations used in the columns ID1 thru ID4. Some data are taken from the PGC 1996 and the NASA/IPAC Extragalactic Database (NED).

Meaning of ther columns:

KDG Number in KDG 1984
N Number of galaxy in the group
ID Primary name of galaxy (NGC, IC or UGC)
Con Constellation
Rekt, Dekl Right ascension, declination (J2000.0)
m Magnitude (in most cases photographic)
a,b Larger and smaler diameter (')
PW Position angle (°)
Typ (Modified) Hubble-type
V Heliozentric radial velocity (km/s)
Dist Distance in Megaparsecs, calculated with H = 67 (km/s)/Mpc (exept NGC 4396, NGC 4406)
PGC Number in the Catalogue of Principal Galaxies (Paturel 1996)
ID1-4 Other designations (in case of insufficient space, a second line is used)


Example of illustration part (printed version)

KDG 189 (Vir)

NGC 5770 13.2 1.7x1.3 120 SB0

NGC 5774 13.0 3.0x2.3 145 Sc

NGC 5775 12.5 4.0x1.1 146 Sb

IC 1066 14.2 1.2x0.7 70 S

IC 1067 13.3 2.0x1.6 110 SBb

IC 1070 15.4 0.6x0.3 130 S


Observing examples:

(1) KDG 184 (in german)

(2) Galaxy groups, Part 1 (in german)