Observed p-HO 1₁₁–0₀₀ spectra (black line and temperature scale) and predicted p-HO 1₁₁–0₀₀ (yellow line and temperature scale) due exclusively to the cool outer material believed to be responsible for the HO absorption. The zero levels are at the same position, but there is a factor of 4 difference in the scales, showing clearly that the absorption from the cool material is far from sufficient to explain the observed absorption. Units are km s^-1 for the velocity and Kelvin for the line temperature. The background is a SCUBA 450 μm image with a linear scale and a peak at 110 Jy/beam. The triangles indicate the positions of the spectra. The open squares indicate the Louvet et al. (2014) sources.