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AsteriaStar
Deep-sky object class · e.g. The Ring Nebula (M57)

Planetary Nebula

The glowing shell of gas cast off by a dying Sun-like star as it becomes a white dwarf, ionised and lit up by the hot stellar core at its centre. Despite the name — coined because their round disks resembled planets in early telescopes — planetary nebulae have nothing to do with planets; they are a brief, beautiful final phase of low- and intermediate-mass stars.

Highlights

  • The cast-off shell of a dying Sun-like star — e.g. the Ring Nebula

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Sources

The primary and reference sources this topic draws on.

  • NASANational Aeronautics and Space Administration

    Mission data, planetary science, space telescopes, and public-domain imagery.

    Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.