Sh 2-71
Sh 2-71 is a planetary nebula in the constellation of Aquila. It is notable for its highly irregular and complex morphology, which has been attributed to interactions within a binary star system, however it is believed the shape and structure of the nebula is formed partially because of a triple star system that has since ejected its third member. The nebula exhibits a broad, asymmetrical ring structure with bipolar lobes and extended emission regions, challenging traditional models of planetary nebula formation driven by single or binary stars. Sh 2-71 is a benchmark object for studying the influence of multiple-star dynamics on the late stages of stellar evolution.