Left: velocity-integrated intensity maps of H41α (gray), H39α (red contour), [C II] 158 μm (green contour), and ¹²CO J = 1 → 0 (blue contour). The contour lines (from thin to thick) are 10% (dashed line), 25%, 50%, 75%, and 90% of the respective peak emissions. The stars indicate the O and B ionizing stars (Beetz et al. 1976; Hanson et al. 1997). The reference position (Δα = 0, Δδ = 0), marked with a cross, is as in Fig. 2. The ultracompact H II region M17-UC1 and four H₂O masers (Johnson et al. 1998) are marked by the circle and “+” symbols, respectively. The small purple circles correspond to the heavily obscured (E_median> 2.5 keV, A_V ≥ 10 mag) population of X-ray sources around the M17-UC1 region (Fig. 10 in Broos et al. 2007; coordinates from the VizieR catalog). Right: same as on the left, but with τ(H I) instead of H39α. All maps have been convolved with a 30′′ beam, to increase the S/N of the H41α map.