¹²CO channel maps of HD 100546. The white and blue lines show the outlines of the hand-drawn masks of the far sides and the nearside, respectively. The white and blue scatter show the corresponding extracted points. The yellow circle denotes the position of the star. To make the fainter parts more visible, a power-law normalization was used. On each panel, the channel velocity in km s⁻¹ is indicated in the top-left corner. The beam size is shown in the bottom-left corner of the first panel.