Channel maps of the 66″-resolution H I cube of NGC 1427A. For visualisation purpose we binned the channels by a factor of 5 compared to the specs given in Sect. 2, resulting in a channel width of 6.9 km s⁻¹. We use a linear grey scale from −2σ to +10σ in order to emphasise the low surface brightness emission, where σ is the noise level. The red contour represents the detection mask used to make the H I moment images.