¹²CO emission velocity channel maps toward IRAS 15398-3359 (gray scale). The upper and lower channel map shows the blueshifted and redshifted emission, respectively, avoiding the central channels around the 5.1 km s⁻¹ cloud velocity. Contours are displayed at 2.0 and 5.0 mJy beam⁻¹. Radial velocities are indicated in the top left corner. Synthesized beam is shown in the bottom left corner on every channel.