| Abstract: | The following arguments suggest that NGC 1275 does not consist of a giant elliptical (E) galaxy that is colliding with (or is superimposed on) a late-type spiral (L): - 1 The total diameter of the region containing young associations is 33 (100/H) kpc. This size is characteristic of ScI galaxies. Neither the morphology nor the integrated luminosity of the L component of NGC 1275 supports such a classification.
- 2 The chaotic appearance of the L component of NGC 1275 is unlikely to be due to tidal damage. This is so because: (a) the E and L components are still approaching each other, (b) their relative velocity is ≈︁ 3000 km s−1, (c) no stripped galaxy core (which would survive a catastrophic tidal encounter) is seen near NGC 1275.
- 3 The core of the Perseus cluster contains only one (anemic) spiral. The a priori probability that NGC 1275 represents a chance superimposition (or collision) of a spiral and an elliptical galaxy is therefore low.
- 4 The assumption that the L component of NGC 1275 is superimposed on, but not interacting with, the E component does not account for (a) the presence of an active SEYFERT nucleus, (b) the peculiar filamentary HII shell, discovered by LYNDS , (c) the presence of recently-formed stars, (d) the X-ray emission and the radio emission of NGC1275.
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