HI contours from Schiminovich et al. (1995). The gas is shown as red contours on an optical r′-band from Gemini. The HII region candidates are indicated by the blue circles. The Gemini image only considers the south tidal debris of the system. This figure shows that the HII sources are detected along the ring of HI contours. The contour levels are 1.9, 3.8, 7.6, and 11.4 × 10¹⁹ cm^-2. The VLA beam is 73″ × 40″.