Abell 39 planetary nebula (blue),optical image. A planetary nebula (nothing to do with a planet) is a shell of gas and dust ejected from a star (centre) near the end of its life. Abell 39 has rare,near-perfect spherical symmetry,is about 5 light-years across,and its shell (white rim) is about a third of a light-year thick. The image is optically filtered to show oxygen ionization by radiation from the central white dwarf star. Abell 39 is 7000 light-years away in the constellation Hercules | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / National Optical Astronomy Observatories |
Taille de l’image : | 1620 px × 1620 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : |
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