NGC 1161 - SA(r)0+

NGC 1161

De Vaucouleurs Atlas Type: SA(r)0+

Filter: B

Telescope: NOT 2.5-m
North left , East down
Field Dimensions: 2.6 x 2.0 arcminutes

RC3 Type: S0
RSA Type: ----
Surface Brightness Range Displayed: 17.5-26.5 mag per square arcsec
Absolute Blue Magnitude: -21.2

De Vaucouleurs Atlas Description:

NGC 1161 is classified as a late S0 because of the strong dust structure near the center. An apparent luminous ring around the center, prominent in the blue light image, is the basis for the (r) classification. However, in the B-V color index map, we see that the appearance of this feature is largely determined by dust. The map shows a complete inner dust ring , enhanced on the near side by tilt effects. The colors are actually bluer inside the dust ring than outside. NGC 1161 is another example of the dust ring phenomenon (Sandage 1961; Sandage and Bedke 1994), with NGC 4429 being most similar.