IC 4290 - (R')SB(r)a

IC 4290

De Vaucouleurs Atlas Type: (R')SB(r)a

Filter: B

Telescope: CTIO 1.5-m
North up , East left
Field Dimensions: 3.4 x 2.8 arcminutes

RC3 Type: (R')SB(r)b
RSA Type: -----
Surface Brightness Range Displayed: 19.5-26.0 mag per square arcsec
Absolute Blue Magnitude: -20.3

De Vaucouleurs Atlas Description:

The bar and inner ring of this galaxy are both exceptional. The bar is strong and shows an inner boxy zone. The inner ring appears to be made of two tightly-wrapped spiral arms. Although the inner ring is exceptionally bright, the outer pseudoring (inset) is exceptionally faint. The outer pseudoring appears to be made of two very faint outer arms winding from near the bar minor axis zone of the inner ring . There is some slight arm doubling in this region. In a B-I color index map (Buta and Crocker 1991), the inner ring is seen to be a very blue feature clearly affected by recent star formation, while the bar shows no evidence for leading dust lanes or nuclear star formation. Faint star-forming regions are also found in the outer pseudoring .

Patsis, Skokos, and Athanassoula (2003) point out that the inner ring of IC 4290 has sharp corners that can interpreted in terms of specific three-dimensional orbit families.