Celestial hemisphere:  Northern  ·  Constellation: Andromeda (And)
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Arp 273 - The Cosmic Rose, 


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Arp 273 - The Cosmic Rose

Getting plate-solving status, please wait...
Arp 273 - The Cosmic Rose, 


Powered byPixInsight

Arp 273 - The Cosmic Rose

Acquisition details

Oct. 14, 2020 ·  Oct. 16, 2020 ·  Oct. 21, 2020
Astrodon 50 mm G: 37×300(3h 5′) (gain: 100.00) -5°C bin 2×2
Astrodon 50mm B: 46×300(3h 50′) (gain: 100.00) -5°C bin 2×2
Astrodon 50mm L: 378×60(6h 18′) (gain: 100.00) -5°C bin 2×2
Astrodon 50mm R: 47×300(3h 55′) (gain: 100.00) -5°C bin 2×2
17h 8′
Flat darks:
Avg. Moon age:
20.43 days
Avg. Moon phase:
Mean SQM:
Mean FWHM:

RA center: 02h21m31s.187

DEC center: +39°2236.10

Pixel scale: 0.196 arcsec/pixel

Orientation: 2.188 degrees

Field radius: 0.084 degrees

More info:Open 

Resolution: 2390x1932

File size: 1.1 MB

Locations: KG Observatory, Julian, CA, United States

Data source: Backyard


At a distance of 300 million light years, this Cosmic Rose was positioned well for 8 hours each evening. I was able to collect lots of subs and discard anything over 2" FWHM. (-:

"Arp 273 lies in the constellation Andromeda and is roughly 300 million light-years away from Earth. The image shows a tenuous tidal bridge of material between the two galaxies that are separated by tens of thousands of light-years from each other.

The larger of the spiral galaxies, UGC 1810, has a disk that is tidally distorted into a rose-like shape by the gravitational tidal pull of the companion galaxy below it, UGC 1813.

The smaller, nearly edge-on companion shows distinct signs of intense star formation at its nucleus, perhaps triggered by the encounter with the companion galaxy.

A series of uncommon spiral patterns in the large galaxy is a tell-tale sign of interaction. The large, outer arm appears partially as a ring, a feature seen when interacting galaxies actually pass through one another. This suggests that the smaller companion actually dived deep, but off-center, through UGC 1810. The inner set of spiral arms is highly warped out of the plane with one of the arms going behind the bulge and coming back out the other side. How these two spiral patterns connect is still not precisely known.

The larger galaxy in the UGC 1810 - UGC 1813 pair has a mass that is about five times that of the smaller galaxy. In unequal pairs such as this, the relatively rapid passage of a companion galaxy produces the lopsided or asymmetric structure in the main spiral. Also in such encounters, the starburst activity typically begins in the minor galaxies earlier than in the major galaxies."


My first attempt in 2018


Sky plot

Sky plot


Arp 273 - The Cosmic Rose,