Hemisphere:  Northern  ·  Constellation: Pegasus (Peg)  ·  Contains:  NGC 7327  ·  NGC 7331  ·  NGC 7333  ·  NGC 7335  ·  NGC 7336  ·  NGC 7337  ·  NGC 7338  ·  NGC 7340

Image of the day 01/17/2022

Getting plate-solving status, please wait...
    NGC 7331 and the "Fleas": Cosmic Linear Perspective, 



    
        

            Howard Trottier
    Powered byPixInsight

    NGC 7331 and the "Fleas": Cosmic Linear Perspective

    Image of the day 01/17/2022

    Getting plate-solving status, please wait...
      NGC 7331 and the "Fleas": Cosmic Linear Perspective, 



    
        

            Howard Trottier
      Powered byPixInsight

      NGC 7331 and the "Fleas": Cosmic Linear Perspective

      Imaging Telescopes Or Lenses
      PlaneWave CDK24
      Imaging Cameras
      FLI Kepler 4040
      Mounts
      PlaneWave L600 Equatorial Configuration
      Filters
      Chroma LRGB
      Software
      PlaneWave Instruments PWI3/PWI4 · PixInsight 1.8.8 Ripley · Software Bisque The Sky X Pro · DC-3 Dreams ACP Expert · Maxim DL 6.20

      Acquisition details

      RA center: 22h37m05s.544

      DEC center: +34°2448.76

      Pixel scale: 0.466 arcsec/pixel

      Orientation: 89.924 degrees

      Field radius: 0.324 degrees

      WCS transformation: thin plate spline

      More info:Open 

      Resolution: 4023x2994

      Data source: Own remote observatory

      Remote source: Sierra Remote Observatories

      Description

      Is there a better example of linear perspective in an astronomical image than one of NGC 7331 and the "Fleas" (collectively referred to as the Deer Lick Group)? A powerful illusion of depth is conveyed by the view out over the foreshortened disk of NGC 7331 through to the four background galaxies known as the fleas (which, from left to right above NGC 7331, are NGC 7337, 7340, 7335, and 7336). Not only is there a chance close alignment of the five galaxies, it also happens that their apparent angular diameters are actually (roughly) inversely proportional to their distances, as would be the case for genuine perspective (implying that the galaxies have roughly the same physical diameter). That is some happenstance! 

      This image is the result of about 30 hours of exposure time, divided roughly equally between luminance and colour. I took about half of the data in the fall of 2020, and the other half at the end of summer 2021. This is the first of the images from my "Final Frontier Telescope" that I've posted at the system's full resolution, which is about 0.47"/pixel, while the FOV here (after lots of "human dithering" over the crop!), is about 31' X 23'.

      I revised the original image that I posted to reduce the "salmon" tint that was in the region around the core, and I backed off on the saturation a bit. I also changed the title to refer to the fleas!

      Comments

      Sky plot

      Sky plot

      Histogram

      NGC 7331 and the "Fleas": Cosmic Linear Perspective, 



    
        

            Howard Trottier