ESO 509-98 - (R1R2')SB(s)a

ESO 509-98

De Vaucouleurs Atlas Type: (R1R2')SB(s)a

Filter: B

Telescope: CTIO 1.5-m
North up , East left
Field Dimensions: 1.9 x 1.4 arcminutes

RC3 Type: (R')SB(s)a
RSA Type: ------
Surface Brightness Range Displayed: 19.0-26.0 mag per square arcsec
Absolute Blue Magnitude: -20.8

De Vaucouleurs Atlas Description:

This galaxy was the first example of the combined ring/pseudoring morphology (R1R2' identified in the CSRG (Buta 1995a). It is an excellent, albeit small, example of its type. The dominant feature is the R2' pseudoring rimming the edge of a bright inner disk, just as in NGC 3358 . The R1 component is weaker but still well enough defined to be recognized. The bar is an excellent ansae type and appears isolated, that is, there is no trace of an inner lens , ring, or pseudoring in this case. NGC 3358 and ESO 509-98 have astonishingly similar azimuthally-averaged surface brightness profiles (Figure 4.6). In each case, the bar and rings are imbedded within a very extended lens -like zone that has a flat surface brightness profile over a significant fraction of the disk.

Figure 4.6
Caption: Azimuthally-averaged blue light surface brightness profiles of NGC 3358 and ESO 509-98 , showing the great similarity.