A Bipolar Nebula


PN Hb 12A bipolar nebula, such as PN Hb 12 shown here, is not one that is off its meds. It’s a distinctive type of nebular formation characterized by an axially symmetric bi-lobed appearance.

The exact cause of this nebular structure is not known, it may be related to a physical process in which a star ejects highly energetic streams of outflow along both poles which may then collide with material surrounding the star, perhaps stellar dust or shells of matter thrown off in a prior supernova event.

Image Credit: NASA