Point Symmetry
It is the first bipolar PPN known to have point reflection symmetry (all others being axially symmetric). Point symmetry is a fairly common trait of planetary nebulae as found in NGC 2022, NGC 2371-2, NGC 6309, Cat's Eye Nebula, NGC 6563, Dumbbell Nebula, Saturn Nebula, A24, and Hb5. Morris & Reipurth 1990 postulate that point symmetry is either due to the bipolar outflow being directed by a precessing disc or a precessing common envelope binary.
Read more about this topic: Frosty Leo Nebula
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