This unusual object was discovered in 1947 [1947PASP...59..257M] by astronomer Rudolph Minkowski and cataloged in his second compilation of new objects. Interestingly he found the nebula during the inspection of objective-prism survey plates through a 10-inch telescope. While the plates, which covers a larger field, shows stars as long and wide lines of their continuous spectra, the emission objects only shows their short emission lines (mostly Hα and [OIII] lines) and so they stand out very well within the field.
Physically the nebula belongs to the group of Proto-Planetary Nebula. The central star (AGB) is dying and produces stellar winds. The star itself is not hot enough to ionize the blown of material and "only" illuminate the gas similar to a reflection nebula. It is suspected, that the bipolar structure is formed by a binary and the gravity between the main red giant and a hot white dwarf. The former APOD shows a spectacular animation of the very fast changes of the appearance of Min 2-9.
In the telescope the nebula is very small and only around 2' long. A 16-inch telescope shows both wings but under very good conditions the bipolar structure could be a target for a 12-inch telescope? What do you think?
I noted:
16", 360x, fst 7m0+, seeing II: small and faint appearance; CS easy and direct visible; faint and thin extensions to N and S, ~1' long
27", 837x, fst 6m5+, seeing III: already elongated object around bright CS with searching eyepiece (113x); with high magnification both wings not uniformly conical but bulgy with knots behind the widest position of the wings, brighter wing and knot to the N; faint but direct visible second star some arc seconds NW of the CS
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