Spectral maps of the N₂H⁺1 → 0 line convolved to an angular resolution of 3.8″. To increase the signal-to-noise ratio, the velocity resolution has been degraded to 12.8 km s^-1. The number in the upper right corner indicates the central channel velocity. First contour and steps are 0.028 K (~ 3 × σ). Crosses indicate the dynamical center of the galaxy and the position of SN 41.9+58.