NGC 5189: An Unusually Complex Planetary Nebula

Explanation: Why is this nebula so complex? When a star like our Sun is dying, it will cast off its outer layers, usually into a simple overall shape. Sometimes this shape is a sphere , sometimes a double lobe , and sometimes a ring or a helix . In the case of planetary nebula NGC 5189 , however, no such simple structure has emerged. To help find out why, the Earth-orbiting Hubble Space Telescope recently observed NGC 5189 in great detail. Previous findings indicated the existence of multiple epochs of material outflow, including a recent one that created a bright but distorted torus running horizontally across image center . Results appear consistent with a hypothesis that the dying star is part of a binary star system with a precessing symmetry axis. Given this new data , though, research is sure to continue. NGC 5189 spans about three light years and lies about 3,000 light years away toward the southern constellation of the Fly ( Musca ).

APOD Editors to Speak: RJN in Philadelphia on Jan. 3 & JTB in New York City on Jan. 4