Distortion scores for clustering on the first (left) and second (right) round of clustering for the 4.9–13.2 μm region in the MIRI MRS dataset as a function of the number of clusters used. The inflection point, or ‘elbow’, in the distortion curve is highlighted with the dashed black line. In the case of the first round of clustering across the entire, cleaned MIRI MRS footprint, four clusters are optimal. In the case of the clustering focused to pixels belonging to the cluster coincident with the atomic PDR, five clusters are optimal.