SuWt 2 is a planetary nebula viewed almost edge-on[2] in the constellation of Centaurus.

It is believed that high UV radiation from an undiscovered white dwarf ionizes this nebula.

Currently, there is a binary system consisting of two A-type main-sequence stars whose radiation is not sufficient to photo-ionize the surrounding nebula.

[3] The nebula is easily obscured by the brighter star, HD 121228.

One of them, which is more massive than other two A-type main-sequence stars, evolved rapidly and became a red giant, swallowing the other two stars, and produced the planetary nebula.