Arp 273, A Rose Made of Galaxies (Sergey Trudolyubov)

Arp 273, A Rose Made of Galaxies

A spectacular pair of interacting galaxies (UGC 1810/UGC 1813), catalogued by Halton Arp as number 273 in his Atlas of Peculiar Galaxies. A high-speed dynamical interaction between the galaxies created an intricate pattern of tidal tails and distorted spiral arms looking like a rose flower. The small apparent size of this photogenic galaxy pair makes it a challenging target for amateur astrophotographers, usually requiring larger apertures, longer focal lengths, stable tracking and good seeing.

This image was taken over several nights in September and November 2020 with my mobile setup: the 250mm f4 Lacerta PhotoNewton and ZWO ASI183MM Pro camera on the Orion HDX-110 EQ-G mount. It was a tough target to both image and process, considering its small apparent size of only 3 arcminutes and mediocre seeing conditions. To combat the effects of poor seeing and get better detail, I resorted to using a combination of short and medium duration luminance exposures (60, 90 and 300 seconds) with different camera gain settings:

L: 8x300s (Gain 0, bin 1x1), 54x90s (Gain 110, bin 1x1), 28x60s (Gain 200, bin 1x1)

R: 32x180s (Gain 110, bin 1x1)

G: 34x180s (Gain 110, bin 1x1)

B: 30x180s (Gain 110, bin 1x1)

Total exposure: 7.3 hours

D

Description: New processing with RC tools. Drizzle x2

Uploaded: ...

E

Description: Wider field, new processing with RC tools. Drizzle x2

Uploaded: ...

F

Description: New processing with RC tools. Drizzle x2 processing, down-sampled back to original bin size. Lighter background.

Uploaded: ...

G

Description: New processing with RC tools. Drizzle x2 processing, down-sampled back to original bin size. Wider field, lighter background.

Uploaded: ...

ZWO ASI183/QHY183
Fast Newtonians
Arp's Peculiar Galaxies

	Distinct awarded users	Total awarded images
Image of the day
Top picks
Top pick nominations

	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
Noctilucent clouds
Landscape

	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
Traveller
Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
Other
Unknown

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Status	Advanced success
Started	...
Astrometry.net job	9190453
PixInsight job	784ESNVH5K4GMML0KY042ED1653CE881
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	02h21m28s.976
RA (top/left)	02h22m20s.755
RA (top/right)	02h20m38s.180
RA (bottom/right)	02h20m37s.337
RA (bottom/left)	02h22m19s.498

Dec (center)	+39°22′32″.75
Dec (top/left)	+39°29′49″.60
Dec (top/right)	+39°30′05″.50
Dec (bottom/right)	+39°15′14″.50
Dec (bottom/left)	+39°14′58″.52

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