The spectrum and structure of 'Minkowski's footprint' - M 1-92

Visual, spectroscopic, and photometric data for M 1-92 are reviewed, and a model is proposed which may account for the bulk of the observational material. According to this model, the emission spectrum observed in this binuclear nebula originates near the central star and is scattered off dust being driven radially outward through the two lobes. It is suggested that the central star is surrounded by a dense flattened circumstellar dust disk as well as by a larger, more tenuous cloud and that the lobes are situated only in the polar regions of the larger cloud. An upper limit of 4.5 kpc is placed on the distance of M 1-92, assuming that the central star has the luminosity of a B0.5 V star.