If a bipolar planetary nebula is viewed exactly pole-on, what shape might its visibility suggest?

Answer

A simple sphere

When a structure that is intrinsically bipolar (like opposing cones) is viewed directly down its axis of rotation (pole-on), the resulting apparent shape observed is that of a simple sphere.

If a bipolar planetary nebula is viewed exactly pole-on, what shape might its visibility suggest?
astronomystarsnebulaeVisibilityplanetary nebulae