Hemisphere:  Southern  ·  Constellation: Crater (Crt)  ·  Contains:  NGC 3981  ·  NGC3981
Getting plate-solving status, please wait...
Arp 289, 



    
        

            Gary Imm
Arp 289, 



    
        

            Gary Imm

Arp 289

Getting plate-solving status, please wait...
Arp 289, 



    
        

            Gary Imm
Arp 289, 



    
        

            Gary Imm

Arp 289

Imaging telescopes or lenses: Celestron EdgeHD 11

Imaging cameras: ZWO ASI 294 MM Pro

Mounts: Astro-Physics Mach1GTO

Guiding cameras: ZWO ASI 174 MM Mini

Software: Adobe Inc Lightroom Classic  ·  Pleaides Astrophoto PinInsight 1.8  ·  Main Sequence Software Sequence Generator Pro  ·  Adobe Inc Adobe Photoshop CC 2021  ·  Stark Labs PHD2 2.6.3

Filters: Astrodon Green 31mm Gen2 I-Series  ·  Astrodon Blue 31mm Gen2 I-Series  ·  Astrodon Lum 31mm Gen2 I-Series  ·  Astrodon Red 31mm Gen2 I-Series

Accessory: Celestron OAG  ·  ZWO EFW 2″X7  ·  MoonLite Focuser for EdgeHD 11


Dates:April 12, 2021April 13, 2021

Frames:
Astrodon Blue 31mm Gen2 I-Series: 30x120" (1h) (gain: 120.00) -20C bin 2x2
Astrodon Green 31mm Gen2 I-Series: 30x120" (1h) (gain: 120.00) -20C bin 2x2
Astrodon Lum 31mm Gen2 I-Series: 60x120" (2h) (gain: 120.00) -20C bin 2x2
Astrodon Red 31mm Gen2 I-Series: 30x120" (1h) (gain: 120.00) -20C bin 2x2

Integration: 5h

Avg. Moon age: 0.80 days

Avg. Moon phase: 0.95%


Astrometry.net job: 4471664

RA center: 11h 56' 7"

DEC center: -19° 53' 52"

Pixel scale: 0.343 arcsec/pixel

Orientation: -0.294 degrees

Field radius: 0.161 degrees


Resolution: 2714x2002

Locations: Backyard (Mag 20.8 - Bortle 4.5), Onalaska, Texas, United States

Data source: Backyard

Description

This object, also known as NGC 3981, is a spiral galaxy located 65 million light years away in the constellation of Crater at a declination of -20 degrees. This magnitude 12 galaxy spans 3 arc-minutes in our apparent view, which corresponds to a diameter of 60,000 light years.

In his Arp catalog, Dr. Arp classified this object into the category of Double Galaxies with Wind Effects. I only see 1 galaxy, so I don’t understand his categorization of this one.

The structure of this galaxy is a beautiful grand design spiral. It is about 10 degrees from edge-on and is colored as you would expect – orange at the core and blue in the arms. There is an interesting large blue region at the bottom of the disk.

I love the extended star streams. This galaxy was disturbed by something but I don’t see any candidates in the vicinity. Perhaps it has already been absorbed.

Comments