Celestial hemisphere:  Northern  ·  Constellation: Camelopardalis (Cam)  ·  Contains:  PGC 138852  ·  PGC 2741324

Image of the day 01/09/2020

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    EGB 4 (Ellis-Grayson-Bond 4), Peter Goodhew
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    EGB 4 (Ellis-Grayson-Bond 4)

    Image of the day 01/09/2020

    Getting plate-solving status, please wait...
      EGB 4 (Ellis-Grayson-Bond 4), Peter Goodhew
      Powered byPixInsight

      EGB 4 (Ellis-Grayson-Bond 4)

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      Description

      EGB 4 (a nebula discovered by Ellis, Grayson, & Bond in 1984) is NOT a comet, despite it's comet-like appearance. It is an emission nebula surrounding a catacylismic binary star system called BZ Cam in the constellation of Camelopardis.

      It has an unusual bow-shock structure as BZ Cam (with it's associated wind) moves through the interstellar medium, similar to the bow wave in front of a ship that is moving through water.

      BZ Cam is believed to be a white dwarf star that is accreting mass from an accompanying main-sequence star of 0.3-0.4 solar masses.

      It is around 2,500 light years away, and has a space velocity of 125 km/second.

      I can only find one previous image of EGB 4 online, a NASA APOD from 2000, so I believe this could be the first amateur image and the first colour image.

      Yes it's ridiculously faint!

      References:

      apod.nasa.gov/apod/ap001128.html

      THE ASTRONOMICAL JOURNAL, 115:286-295, 1998 January © 1998. The American Astronomical Society.

      aanda.org/articles/aa/full/2001/36/aa1385/aa1385.right.html

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        EGB 4 (Ellis-Grayson-Bond 4), Peter Goodhew
        Original
        EGB 4 (Ellis-Grayson-Bond 4), Peter Goodhew
        B
      • Final
        EGB 4 (Ellis-Grayson-Bond 4), Peter Goodhew
        C

      B

      Description: star colour

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      EGB 4 (Ellis-Grayson-Bond 4), Peter Goodhew