Pseudobulges: NGC 4826

NGC 4826 is an Sb galaxy in which spiral structure dominates the "bulge" part of the brightness distribution. At left is the V-band CFHT image that was used in the color composite on the previous page. It is shown here with apparent brightness proportional to the logarithm of the true brightness so that features can be seen over a large range in radius. The central parts are shown in more detail in the V-band, PSF-deconvolved Hubble Space Telescope image at right (Lauer et al. 1995, AJ, 110, 2622). The region shown is about 17 arcsec wide, and the brightness stretch is also logarithmic. Since we see spiral features at all radii, cold disk material and not an elliptical-galaxy-like bulge dominates even very near the center where the steep brightness profile would otherwise make us think that there is a bulge.

NGC 4736 is another example.

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Last update: February 7, 2000

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