Helix Nebula (NGC 7293), optical image. This is a planetary nebula, a series of shells of gas cast off by a dying star. The ejection of the star's out

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Helix Nebula (NGC 7293), optical image. This is a planetary nebula, a series of shells of gas cast off by a dying star. The ejection of the star's outer layers exposes its hot core, whose radiation ionises the shells, causing them to glow. The Helix Nebula is 650 light years from Earth, in the constellation of Aquarius. This image includes filters for the light from hydrogen (H-alpha), oxygen (OIII) and sulphur (SII) ions.

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Size: 3458px × 2539px
Photo credit: © DR LUKE DODD/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 7293, alpha, aquarius, astronomical, astronomy, astrophysical, astrophysics, dust, evolution, gas, halpha, helix, hydrogen, ionised, nebula, ngc, night, oiii, optical, oxygen, planetary, sii, sky, space, stellar, sulfur, sulphur, telescope, universe, visible