Left: column density map of G18.82-0.28, obtained from SED-fit to Herschel 160, 250, 350, 500 μm data. Black contours indicate the levels N_dust = 2 to 5 × 10²² cm^-2 in steps of 10²² cm^-2, white-dashed contour outlines the approximate completeness level, and ellipse is taken from Simon et al. (2006b), defining the IRDC. Right: line integrated ¹³CO 1→0 emission in colour scale (in [K km s^-1]) between v = 61 and 70 km s^-1, the velocity range of the bulk emission of G18.82-0.28 and the associated GMC. Note that this GMC was already identified as a coherent cloud complex in Schuller et al. 2009. The Herschel H₂ column density is overlaid as black contours (levels 1,2,3,4,5 × 10²² cm^-2) and the IRDC is outlined by an ellipse (Simon et al. 2006b).