Bubble nebula (NGC 7635), optical image. This nebula is named for the circular shell of gas (blue) at centre. This hollow shell has been excavated out

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Bubble nebula (NGC 7635), optical image. This nebula is named for the circular shell of gas (blue) at centre. This hollow shell has been excavated out of the surrounding nebula by the powerful stellar wind of a massive star within it. The entire nebula glows as the gases it contains are ionised by radiation from hot young stars that have formed within it. Different colours have been assigned to different ionised gases here; sulphur is red, hydrogen is green and oxygen is blue. The nebula lies some 11,000 light years from Earth in the constellation Cassiopeia.

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Size: 3817px × 2545px
Photo credit: © RUSSELL CROMAN/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 2005, 7635, astronomical, astronomy, astrophysical, astrophysics, birth, bubble, cassiopeia, circle, circular, emission, evolution, formation, gas, gases, hydrogen, ionised, nebula, ngc, oxygen, space, star, starbirth, stellar, sulfur, sulphur, telescope