Celestial hemisphere:  Southern  ·  Constellation: Cetus (Cet)
Getting plate-solving status, please wait...
Arp 121, 



    
        

            Gary Imm
Arp 121, 



    
        

            Gary Imm

Arp 121

Getting plate-solving status, please wait...
Arp 121, 



    
        

            Gary Imm
Arp 121, 



    
        

            Gary Imm

Arp 121

Acquisition details

Dates:
Aug. 12, 2021 ·  Aug. 13, 2021
Frames:
Astrodon Gen2 I-Series Tru-Balance Blue: 30×120(1h) (gain: 120.00) -10°C bin 2×2
Astrodon Gen2 I-Series Tru-Balance Green: 30×120(1h) (gain: 120.00) -10°C bin 2×2
Astrodon Gen2 I-Series Tru-Balance Lum: 60×120(2h) (gain: 120.00) -10°C bin 2×2
Astrodon Gen2 I-Series Tru-Balance Red: 30×120(1h) (gain: 120.00) -10°C bin 2×2
Integration:
5h
Avg. Moon age:
4.56 days
Avg. Moon phase:
21.92%

RA center: 00h59m23s.981

DEC center: -04°4808.55

Pixel scale: 0.345 arcsec/pixel

Orientation: 83.776 degrees

Field radius: 0.135 degrees

More info:Open 

Resolution: 2306x1635

File size: 1.2 MB

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

Data source: Backyard

Description

This Astrobin Debut Object is a pair of interacting galaxies located 200 million light years away in the constellation of Cetus at a declination of -5 degrees.   In his Arp catalog, Dr. Arp classified this object into the category of Elliptical and Elliptical-like Galaxies Close to and Perturbing Spirals. 

The edge-on spiral galaxy is LEDA 3547.  This magnitude 15 object spans 2 arc-minutes in our apparent view, which corresponds to a Milky Way size diameter of 120,000 light years.

The elliptical galaxy is LEDA 3553.   This magnitude 16 object is half as large as its companion, with a diameter of 60,000 light years.

I love the star plumes surrounding these 2 galaxies, leaving little doubt that they are interacting.  The plume extends from the lower left to the upper right.

My favorite part of the image is the lovely disturbed disk of the edge-on spiral, outlining not one but two sine wave shapes.  The mid-line dust lane varies in thickness along its length and is highlighted by a subtle blue star cluster or star cloud, seen on the right side slightly above the dust lane.  The spiral core is slightly offset to the left.

In contrast to the spiral, the elliptical galaxy appears fairly undisturbed.

Comments