NGC 7009, Saturn Nebula, Composite
The Saturn Nebula or NGC 7009 is a planetary nebula in the constellation Aquarius. It appears as a greenish-yellowish hue in a small amateur telescope. The Saturn Nebula is a complex planetary nebula and contains many morphological and kinematic sub-systems in three dimensions. It includes a halo, jet-like streams, multiple shells, ansae (handles), and small-scale filaments and knots. The ansae are expanding non--adially from the central star. X-ray emission from Chandra is colored purple and optical emission from the Hubble Space Telescope is colored red, green and blue. A planetary nebula is a phase of stellar evolution that the sun should experience several billion years from now, when it expands to become a red giant and then sheds most of its outer layers, leaving behind a hot core that contracts to form a dense white dwarf star. A wind from the hot core rams into the ejected atmosphere, creating the shell-like filamentary structures seen with optical telescopes. The diffuse X-ray emission is caused by shock waves as the wind collides with the ejected atmosphere. The properties of the X-ray point sources in the center of about half of the planetary nebulas suggest that many central stars responsible for ejecting planetary nebulas have companion stars. Release date October 10, 2012.
Size: 4200px × 2771px
Photo credit: © Photo Researchers / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: 2012, 21st, 7009, astronomical, astronomy, body, celestial, century, cloud, composite, deep, emission, heavenly, image, interstellar, nebula, nebulae, ngc, object, planetary, region, saturn, science, sky, space, star-forming, stellar-remnant
