Hemisphere:  Northern  ·  Contains:  PK085+04.1  ·  Sh2-115  ·  Sh2-116

Image of the day 10/05/2021

Getting plate-solving status, please wait...
    Sh2-115 and the wannabe planetary nebula Sh2-116, 



    
        

            Jonathan Piques
    Powered byPixInsight

    Sh2-115 and the wannabe planetary nebula Sh2-116

    Image of the day 10/05/2021

    Getting plate-solving status, please wait...
      Sh2-115 and the wannabe planetary nebula Sh2-116, 



    
        

            Jonathan Piques
      Powered byPixInsight

      Sh2-115 and the wannabe planetary nebula Sh2-116

      Imaging telescopes or lenses: Orion optics UK AG12

      Imaging cameras: zwo optical ASI 2600MM Pro

      Mounts: Software Bisque Paramount MX+

      Guiding telescopes or lenses: Orion optics UK AG12

      Guiding cameras: ZWO ASI290 Mini

      Software: PIXINSIGHT 1.8  ·  Sequence Generator Pro

      Filters: Chroma Ha 5nm 36mm  ·  Chroma OIII (3nm)  ·  Astrodon S-II 36mm - 3nm

      Accessory: StarLight Instruments Feather Touch Focuser  ·  Pegasus Astro ultimate powerbox v2


      Dates:Sept. 18, 2021Sept. 20, 2021Sept. 22, 2021

      Frames:
      Astrodon S-II 36mm - 3nm: 27x600" (4h 30') (gain: 100.00) bin 1x1
      Chroma Ha 5nm 36mm: 44x600" (7h 20') (gain: 100.00) bin 1x1
      Chroma OIII (3nm): 49x600" (8h 10') (gain: 100.00) bin 1x1

      Integration: 20h

      Avg. Moon age: 14.25 days

      Avg. Moon phase: 96.83%


      RA center: 20h34m18s.859

      DEC center: +47°0159.94

      Pixel scale: 0.684 arcsec/pixel

      Orientation: -175.390 degrees

      Field radius: 0.589 degrees

      More info:Open 


      Resolution: 4781x3958

      Data source: Own remote observatory

      Remote source: DeepSkyWest

      Description

      This image showcases two nebulae from the Sharpless catalog.  The first, Sharpless 115, is the larger of the two, and dominates the upper right hand of the image. It is a surprisingly faint emission nebula somewhere around 7,500 light years away. Much of the ionization within the nebula is caused by the relatively young ("only" 100 million years old) stars in the open cluster Berkeley 90, also found within the nebula. 

      You'll also notice a sneaky little marble in the bottom left of the image, and this is Sharpless 116, also cataloged as Abell 71. For many decades, this was thought to be a planetary nebula, but a study published in the 1990s contends that it is actually a HII region.  Regardless of its origin, it makes for some additional visual interest in what is already a complex field, i.e. it's cute. 

      This was a fairly straightforward emission nebula in terms of processing, though it was unique in that there was good representation across all three spectra.  The Ha signal dominated, though it was fainter than some other similar nebulae, Oiii was similarly faint but definitely present, and Sii surprisingly strong.  In terms of aesthetics, I really wanted to emphasize all three spectra and their contributions to the image: so often emission nebulae are so overwhelmed with Ha that it makes it a little monolithic and challenging to make interesting.  For this one, I chose a color palette that reflects the contributions of all three, and processed it to highlight the busy interior structure of the nebula.  Hopefully I did it some measure of justice. It had been a while since I've done a Hubble palette-esque image so it took me a minute to get the hang of it again.  As always, C&C are welcome.

      Comments

      Sky plot

      Sky plot

      Histogram

      Sh2-115 and the wannabe planetary nebula Sh2-116, 



    
        

            Jonathan Piques