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Advancements in infrared IR open up the possibility to spatially resolve AGNon the parsec-scale level and study the circumnuclear dust distribution,commonly referred to as the "dust torus", that is held responsible for the type1/type 2 dichotomy of AGN. We used the mid-IR beam combiner MIDI together withthe 8m telescopes at the VLTI to observe the nucleus of the Seyfert 2 galaxyNGC 424, achieving an almost complete coverage of the uv-plane accessible bythe available telescope configurations. We detect extended mid-IR emission witha relatively baseline- and model-independent mid-IR half-light radius of (2.0\pm 0.2) pc \times (1.5 \pm 0.3) pc (averaged over the 8-13 {\mu}m wavelengthrange). The extended mid-IR source shows an increasing size with wavelength.The orientation of the major axis in position angle -27deg is closely alignedwith the system axis as set by optical polarization observations. Torus modelstypically favor extension along the mid-plane at mid-IR wavelengths instead.Therefore, we conclude that the majority of the pc-scale mid-IR emission(>~60%) in this type 2 AGN originates from optically-thin dust in the polarregion of the AGN, a scenario consistent with the near- to far-IR SED. Wesuggest that a radiatively-driven dusty wind, possibly launched in a puffed-upregion of the inner hot part of the torus, is responsible for the polar dust.In this picture, the torus dominates the near-IR emission up to about 5 {\mu}m,while the polar dust is the main contributor to the mid-IR flux. Our results ofNGC 424 are consistent with recent observations of the AGN in the Circinusgalaxy and resemble large-scale characteristics of other objects. If ourresults reflect a general property of the AGN population, the current paradigmfor interpreting and modeling the IR emission of AGN have to be revised.(abridged)

Parsec-scale dust emission from the polar region in the type 2 nucleus of NGC 424