NGC 3261 - SB(rs)b

NGC 3261

De Vaucouleurs Atlas Type: SB(rs)b

Filter: B

Telescope: CTIO 0.9-m
North up , East left
Field Dimensions: 4.1 x 3.0 arcminutes

RC3 Type: SB(rs)b
RSA Type: SBab(rs)I-II
Surface Brightness Range Displayed: 18.5-26.0 mag per square arcsec
Absolute Blue Magnitude: -21.5

De Vaucouleurs Atlas Description:

The bar, inner pseudoring , and outer spiral are all well-defined. We base the Sb classification on the bright spiral region extending to about twice the inner ring radius. These arms are moderately open and patchy, and are typical of the Sb type. Beyond this inner spiral region, the arms are much more open and would favor a later type. NGC 3261 appears also to have a significant bulge, with no nuclear ring or obvious leading dust lanes. We use the underline notation to indicate that the inner pseudoring almost closes; the ring appears to be made of two clear spiral arms. The way these arms appear to begin at approximately 40o to the bar axis suggests that this might be a case where the bar and the spiral have different pattern speeds (Sellwood and Sparke 1988).