Intensity of the far-infrared fine-structure lines [C II]λ158 µm (left) and [O III]λ88 µm (right) in W m⁻² sr⁻¹, observed by SOFIA/FIFI-LS. The intensities are the result of spectral Gaussian fits and only those fits with a S/N ≥ 3 are shown. Pixels with lower S/N are displayed as 0 (in black). The white contours are from L_TIR (300 and 600 L_so//pc²) shown in Fig. 3. The thin black contours shown in the [C II] map are 8 µm from Spitzer/IRAC (4 and 8 MJy/Sr). The red contours in the [O III] map are Spitzer/MIPS 24 µm continuum (5 and 150 MJy/sr). The [C II] map is shown in the native resolution with a beam FWHM of 15.3″. The [O III] data in the three bright star formation regions marked by dashed blue, green and red lines was smoothed to the same resolution (15.3″) to increase the S/N per beam. Outside of the regions the data was further re-binned to 24″ and fit within a 48″ beam to further increase the S/N in the diffuse regions. The seven gray crosses, in identical positions in the [C II] and [O III] maps, mark the positions of the spectra shown in Appendix A.