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Messier 74

Spiral Galaxy in the Constellation Pisces

Discovered 1780 by Pierre Méchain.  Messier 74 (M74, NGC 628) is one of the nicest examples of so-called "grand-design" spiral galaxies seen face-on, so that its spiral structure stands out conspicuously. With its comparatively low surface brightness, it is one of the more difficult objects in Messier's catalog visually, situated in constellation Pisces.  This conspicuous spiral is a prototype of a grand-design Sc galaxy.  Its distance may be about 30 to 40 million light years.  It is receding from us at a speed of 793 km/sec.  Its spiral arms are about 10,000 light years broad. They are traced with clusters of blue young stars and pinkish colored diffuse gaseous nebulae (H II regions) in color photos, and reach out to cover a region of more than 10 minutes of arc in diameter, corresponding to roughly 95,000 light years, or about the same size as our Milky Way galaxy.

 
Image Details:

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  • Instrument: Stellarvue SV130EDT Triplet APO Refractor @ f/7(905mm) focal length, with Teleskop Service TS 2,5 Field Flattener lens.
  • Mount:  Rainbow Astro RST-135 Mount in EQ Mode R
  • Image Scale:  1.08 arc-seconds/pixel
  • Camera: ASI071MC Pro Color Cooled One-Shot Camera with Lumicon IR/Cutoff Filter
  • Guide and Imaging Interface: ASI290MM guide camera and ZWO Off-Axis Guider, ASIAir Plus Controller, ZWO EAF Auto-Focuser.
  • Filters & Exposure Times:  RAW format 16-bit Light frames with IR/Cutoff filter.  230 sub-frames x 3 minutes each, binned 1x1.  Total exposure time of 11.5 hours.
  • Processing software: PPixInsight, using a combination of the ChaoticNebula.com and Adam Block workflows.
  • Location: Little Rock, AR., El. 537ft
  • Date: Image Acquisition January 23-24th, 2022

© Wade Van Arsdale
2/07/2022

Earlier Version of M74 from 2011

Image Details:

•  
  • Instrument:  Planewave Instruments CDK 12.5 with Astro-Physics AP27TVPH focal reducer @ f/6.2 (1971mm)
  • Mount:  AP1200GTOCP3
  • Image Scale:  1.2 arc-seconds per pixel after processing
    Camera: SBIG ST-2000XM with AO8 Adaptive Optics and CFW10 Color Filter Wheel using Custom Scientific LRGB filters 
    Filters & Exposure Times:
    • L:  18 x 5 minutes binned 1 x 1
    • R:  24 x 5 minutes binned 1 x 1
      G:  12 x 5 minutes binned 1 x 1
      B:  18 x 5 minutes binned 1 x 1
    • Super-Luminance Layer used for L-[LRGB]-RGB Stacking
    • Multiple Luminance Layering in Photoshop (technique as described by Rob Gendler)
    • Total equivalent unbinned exposure time of 10.5 hours
    Software: Maxim DL/CCD, CCDStack, Adobe Photoshop CS2, RC Astro Gradient X-Terminator
    Location:  C.A.A.S. East Observatory, Little Rock, AR., El. 650ft
    Date: January 29th, 2011

Wade Van Arsdale
Little Rock, AR., USA
February 5th, 2011