What interaction primarily determines the dramatic structure of a planetary nebula?
Answer
The fast wind slamming into the slow wind.
The dramatic structures observed in planetary nebulae result from the pressure and shock created when the high-speed material ejected by the fast wind slams into the cooler, slower material ejected previously.

#Videos
Here's Why Planetary Nebulae Look So Different...But ... - YouTube
Related Questions
What interaction primarily determines the dramatic structure of a planetary nebula?Approximately how fast is the initial, slow stellar wind shed by an AGB star?What is the potential speed of the second, fast stellar wind?How can a binary companion star influence the expanding gas of a planetary nebula?According to field dynamics, how do magnetic fields influence the outflowing plasma?What is the common mechanism across theories involving companions or magnetic fields that shapes the nebula?Approximately how long does the luminous phase that creates the visible planetary nebula typically last?Observing a highly knotted or clumpy nebula suggests what about the star's mass ejection history?What structure does the presence of clear rings or tight tori intersecting the central axis of a nebula indicate?For a planetary nebula to result in a perfectly round shape, what conditions must be met regarding the stellar winds?What stage precedes the formation of a planetary nebula?