The NASA/IPAC EXTRAGALACTIC DATABASE (NED) lists galaxies from the European Southern Observatory (ESO) catalog as G (ESO 012- G 014) or IG (ESO 293-IG 034).
What does G/IG signify?
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Sign up to join this communityThe NASA/IPAC EXTRAGALACTIC DATABASE (NED) lists galaxies from the European Southern Observatory (ESO) catalog as G (ESO 012- G 014) or IG (ESO 293-IG 034).
What does G/IG signify?
These identifiers correspond to the ESO/Uppsala Survey of the ESO(B) Atlas (1982). The identifier column (ESO) is associated with the following note:
Note (1) : ESO designation is written FFF-oooNNN, where FFF = Field (plate) number, see file "plates.dat" ooo = Object class with * = star ** = double or multiple star SC = star cluster N = nebula A = asteroid C = comet G = galaxy IG = interacting galaxy EN = emission nebula PN = planetary nebula RN = reflection nebula SNR = supernova remnant ? = questionable object NNN = number within field
So the "G" means "galaxy" and "IG" means "interacting galaxy".