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Thread: IC 4678 is there any scientific explanation for this straight nebula

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    Question IC 4678 is there any scientific explanation for this straight nebula



    Hi

    I took an image of M8 nebula and noticed this strange IC 4678 ( attached )..
    My question is : Why this nebula looks like a straight line cut ?
    All other nebula has a random shape.. but not a LINE shape !! any reason ?

    Thanks
    Attached Images Attached Images
    Skywatcher Refractor ED100, Orion Refractor 80mm,Orion Atlas EQ-G mount, Lacerta standalone auto guider, Modified dslr Canon 700d, Astronomik CLS filter..

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    Default Re: IC 4678 is there any scientific explanation for this straight nebula

    Very nice M8!

    Actually no nebula has a random shape!

    For reflection and emission nebulas both they would be spherically shaped if the gas in the area had a constant density. All deviations from sphericity are due to variations in the density of gas in the neighborhood. Variations in temperature also play a role. Here is a larger scale image that shows more detail.

    https://apod.nasa.gov/apod/ap050524.html

    You'll see it's less straight in this larger scale image in which the straight edge looks like a large radius curve on the emission side convex, on the reflection side concave. Emission nebulas shape and curvature are given by the concept Stromgren sphere.

    https://en.m.wikipedia.org/wiki/Str%C3%B6mgren_sphere

    In this case it's a BIG one.

    The other side of the reflection nebula just looks like it's running out of gas density or obscured by lower temperature gas.
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    Default Re: IC 4678 is there any scientific explanation for this straight nebula

    Quote Originally Posted by not_Fritz_Argelander View Post
    Very nice M8!

    Actually no nebula has a random shape!

    For reflection and emission nebulas both they would be spherically shaped if the gas in the area had a constant density. All deviations from sphericity are due to variations in the density of gas in the neighborhood. Variations in temperature also play a role. Here is a larger scale image that shows more detail.

    https://apod.nasa.gov/apod/ap050524.html

    You'll see it's less straight in this larger scale image in which the straight edge looks like a large radius curve on the emission side convex, on the reflection side concave. Emission nebulas shape and curvature are given by the concept Stromgren sphere.

    https://en.m.wikipedia.org/wiki/Str%C3%B6mgren_sphere

    In this case it's a BIG one.

    The other side of the reflection nebula just looks like it's running out of gas density or obscured by lower temperature gas.
    Thanks for your simple and straight answer..
    I always jump the fact that nebulas are 3D
    and that because we are dealing with 2D images.. now I got the real picture
    Skywatcher Refractor ED100, Orion Refractor 80mm,Orion Atlas EQ-G mount, Lacerta standalone auto guider, Modified dslr Canon 700d, Astronomik CLS filter..

 

 

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