What perturbs NGC 2188?

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VLA HI observations of the dwarf irregular galaxy NGC 2188 show that the gas and stars have spatial distributions which are substantially different. One end of the optical disk is strongly gas deficient, while neutral gas extends into the halo over distances of more than 2 kpc from the midplane. This and the peculiar velocity field suggest that NGC 2188 is a perturbed system, although it is not obviously an interacting galaxy. In addition, NGC 2188 is remarkable for its interstellar disk-halo connection. An Halpha image of NGC 2188 shows the presence of spectacular features of ionized gas extending from a large star-forming complex up to 500 pc into the halo. Also, peculiar HI filaments and at least one superbubble are present in NGC 2188.