Optical CCD (Charge Coupled Device) image of the Ring Nebula M57 (NGC 6720) which is situated in the constellation of Lyra and is one of the finest pl

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Optical CCD (Charge Coupled Device) image of the Ring Nebula M57 (NGC 6720) which is situated in the constellation of Lyra and is one of the finest planetary nebulae. The image was taken at the particular wavelength of red hydrogen light (6560 Angstroms) and is the result of the superimposition of two different images. M57 is composed of a shell of gas ejected by a hot central star, the red dot at the centre, which is probably a white dwarf, the final stage of stars such as our Sun. The shell is expanding at a velocity of about 20km per second and it is glowing due to the ultraviolet radiation of the central star which ionises the gas in the shell.

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Size: 3697px × 2481px
Photo credit: © DR RUDOLPH SCHILD/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 6720, astronomy, cosmology, death, m57, mgc, nebula, ngc, planetary, ring, science, star, stellar