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NGC 55:

The brightness distribution is very asymmetrical. There is no visible nucleus.


The region within about 10" of the nucleus is interesting. Either there are several radial dust lanes, or the luminous matter is concentrated in five or six discrete clumps, creating a flower-like pattern. The streak on the plate is due to a baffle problem.


The eastern spiral arm branches near its end into two components of approximately equal surface brightness and length, which diverge at an apparent angle of between 30 and 40°.


Seyfert galaxy. Short exposures show complex spiral structure in the inner region.


The nuclear region is remarkably complex. There is a bright spot at the center, surrounded by a fairly uniform disk of lower surface brightness about 10" in diameter. About the disk are concentrated a large number of distinct condensations, at least 15 of which can be seen on the present plate, most of which are of very high surface brightness, and several of which are < 1" in size. Thecondensations appear to be arranged in a "spiral" pattern, the overall diameter of which is about 25". There is a faint elliptical companion galaxy.


The nucleus is somewhat asymmetrical, which may indicate the presence of dust.


The nucleus consists of a bright spot surrounded by a disk of somewhat lower surface brightness. This situation introduces a slight ambiguity in the Yerkes "population group" classification.


The system is reminiscent of the Large Magellanic Cloud, although it is somewhat more highly organized and has a definite nucleus. There is an enormous complex of ionized gas in one arm, which is resolved into 5 or 6 sub-condensations on the present plate.


The radio source Fornax A. There are "chains" of dark clouds in the inner region of this unusual system, and dark lanes emanate from the nucleus near the minor axis.


The bar is located within the nuclear disk.


The bar and ring structure, and the spiral arms, are very faint relative to the large, amorphous nucleus. With just slightly less information, this galaxy might be mistaken for an elliptical.


There is possibly some dust north of the nucleus, but a somewhat longer exposure is needed to be certain.


There may be a bar within the nuclear disk. The difference between D and E types is strikingly shown by comparing figures 15 and 16.


Seyfert galaxy. The inner nucleus is essentially stellar on a 5-minute exposure; longer exposures show an amorphous disk surrounding it. The inner regions are therefore entirely different from those in NGC 1068. The condensations along the relatively short, inner spiral arms are extremely bright; remarkably, the two brightest are found just at the ends of these arms. The one near the end of the eastern arm may look almost stellar at first glance, but some structure is visible in it on the original plate. Dust lanes are clearly visible along the inner edges of the arms.


The spiral structure of this galaxy, if it can be called that, is very chaotic. The small nucleus is no brighter than many of the condensations in the body of the galaxy.


Three primary nuclear "hot spots" appear to be connected by high-surface-brightness filaments, and the whole ensemble is inscribed in a disk of somewhat lower surface brightness. The dust pattern has peculiar radial components.


Although the system is nearly edge-on, two linear dust lanes suggest that it is a barred spiral like NGC 1097 and NGC 1300.


A complex or disturbed spiral system; unfortunately the high inclination renders interpretation difficult. No definite nucleus can be seen.

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