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Image of the day 04/22/2021

The Coma Cluster (Abell 1656) and Dragonfly 44, 



    
        

            Chen Wu
The Coma Cluster (Abell 1656) and Dragonfly 44
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The Coma Cluster (Abell 1656) and Dragonfly 44

Image of the day 04/22/2021

The Coma Cluster (Abell 1656) and Dragonfly 44, 



    
        

            Chen Wu
The Coma Cluster (Abell 1656) and Dragonfly 44
Powered byPixInsight

The Coma Cluster (Abell 1656) and Dragonfly 44

Acquisition details

Dates:
March 6, 2021 ·  March 14, 2021 ·  March 17, 2021 ·  March 18, 2021 ·  March 31, 2021
Frames:
Chroma B 50mm: 46×300(3h 50′) (gain: 0.00) -10°C bin 1×1
Chroma G 50mm: 46×300(3h 50′) (gain: 0.00) -10°C bin 1×1
Chroma Lum 50mm: 161×300(13h 25′) (gain: 0.00) -10°C bin 1×1
Chroma R 50mm: 46×300(3h 50′) (gain: 0.00) -10°C bin 1×1
Integration:
24h 55′
Darks:
20
Flats:
20
Bias:
20
Avg. Moon age:
9.96 days
Avg. Moon phase:
34.56%
Bortle Dark-Sky Scale:
2.00
Temperature:
10.00

Basic astrometry details

Astrometry.net job: 4390538

RA center: 13h00m26s.4

DEC center: +27°5703

Pixel scale: 1.545 arcsec/pixel

Orientation: 77.449 degrees

Field radius: 0.505 degrees

Resolution: 1413x1884

File size: 884.6 KB

Locations: Dark Sky New Mexico, Animas, New Mexico, United States

Data source: Own remote observatory

Remote source: Dark Sky New Mexico

Description

Spoiler: Dragonfly 44 is not presented in the original revision but revision E.

I came to learn about Dragonfly 44 back in maybe 2017 through Sky & Telescope. A research team assembled 10+ Canon 400mm f2.8 lens array from a remote dark site. They made the discovery and took the picture of the unknown diffuse galaxy at that time.

I recall I read that even the Hubble telescope scanned the region five times before locating the object. I couldn't find the citation now.

Wiki says its magnitude is about 21. It's way far beyond my reach when I was shooting from backyard or even from our club's dark site (class 4). I have been salivating though it was obviously a quite luxurious thought to take a picture of it.

Now it's a totally different story. Being at one of the best remote sites, our 300s gain 0 lum subs (asi6200mm) can easily capture mag 22+ targets after integration. Even squeezing MaskGen in PixInsight with the latest DR3 database to its very limit couldn't cover the tiniest stars in our masters. Interestingly, my friend Joe has made a successful attempt last year after two whole nights of imaging.



I figured it's time to see the limit of our equipment and seeing condition. Though this target is about Abell 1656 (Coma Cluster), the full FOV is intentionally oriented to accommodate the dark target. There is no crop in revisions E/F.

I'd say under our class 2 sky, the performance of the optics is expected. Besides this faint Dragonfly 44, a lot other objects are on par or even darker. Enjoy finding and looking!

Ps, Hubble/ESA released the data of NGC 4291 in 2016 and a magnificent processing won APOD in 2019.



It is the grand design spiral galaxy in the lower central part of my picture.

#TeamNoctuaDSNM

Comments

Revisions

  • Final
    The Coma Cluster (Abell 1656) and Dragonfly 44, 



    
        

            Chen Wu
    Original
    The Coma Cluster (Abell 1656) and Dragonfly 44, 



    
        

            Chen Wu
    E
    The Coma Cluster (Abell 1656) and Dragonfly 44, 



    
        

            Chen Wu
    F

E

Description: Full FOV (asi6200mm) on TOA130

Uploaded: ...

F

Description: Full FOV with annotation

Uploaded: ...

Sky plot

Sky plot

Histogram

The Coma Cluster (Abell 1656) and Dragonfly 44, 



    
        

            Chen Wu

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