Shapley 1: An Annular Planetary Nebula

Astronomy Picture of the Day · 1997-02-15 · NASA (public domain)

Shapley 1: An Annular Planetary Nebula — APOD for 1997-02-15

Explanation : What happens when a star runs out of nuclear fuel ? The center condenses into a white dwarf while the outer atmospheric layers are expelled into space and appear as a planetary nebula . This particular planetary nebula , designated Shapley 1 after the famous astronomer Harlow Shapley , has a very apparent annular ring like structure. Although some of these nebula appear like planets on the sky (hence their name), they actually surround stars far outside our Solar System .

Astronomy Picture of the Day for 1997-02-15 — image & explanation courtesy of NASA (public domain), mirrored at Tukuk-OS for reading and search convenience.