Selected channel maps of the GBT data cube. Contour levels are −2σ (gray dashed contours) and (2,4,8,16,32,64,128,256,512,1024)σ (full contours) where σ = 6 mJy beam^-1. This corresponds within a single channel to a column density of 1.25 × 10¹⁷ cm^-2. Heliocentric velocities of the channels in km s^-1 are shown in the top-right of each channel. From 150.5 to 104.1 km s^-1 every channel is shown. Outside this range only every third channel is shown. The GBT beam is shown in the bottom-left corner of the top-left panel. Channels in the bottom row are marginally affected by Galactic emission. In the 140.2 km s^-1 panel the arrow indicates cloud emission.