NEBULAE & STAR CLUSTERS
A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

                  
  • HOME
  • ABOUT
  • CATEGORIES
  • SITE MAP
  • COPYRIGHT
  • ADVERTISE
  • CONTACT


  • entire Web this site



    Egg Nebula (CRL 2688)

    Egg Nebula (CRL 2688)
    A protoplanetary nebula in the constellation Cygnus. The central star of the Egg was a red giant until a few hundred years ago. It then began shedding its outer layers, which today are visible as a cloud of matter about 0.6 light-year across.

    Observations by the Hubble Space Telescope have shown bright arcs of matter within the cloud, almost like tree-rings, that reveal the way in which the rate of mass ejection from the central star has varied throughout its recent period of mass-loss. Hubble has also shown starlight escaping in narrow, oppositely-directed beams through holes in the circumstellar cocoon. The beams may result from shadows cast by blobs of material distributed within the region of ring-like holes that are carved out by a wobbling, high-speed stream of matter. Alternatively, they may be due to starlight reflected off fine jet-like streams of matter being ejected from the center and confined to the walls of a conical region around the symmetry axis. Both theories call for the ejection of high-speed material in a narrow beam by some mechanism that isn't properly understood. Similar fine jets have been seen in the Cat’s Eye Nebula.


    Visual magnitude 13.5
    Angular size 30" × 15"
    Distance 3,000 light-years
    Position R.A. 21h 02.3m, Dec. +36° 42'


    Related category

       • NEBULAE AND STAR CLUSTERS



    Also on this site:

    Encyclopedia of Alternative Energy & Sustainable Living
    Encyclopedia of History
    Transport Concepts & Designs (partner site)



    BACK TO TOP