Arp 295: A Galactic Hand-Shake

OTA: CDk24
Camera: Morovian 61000 Pro
Observatory: Heaven's Mirror
Date of Capture: Nov, '23
Date of Processing: Nov,' 23

Exposures:
R: 16 x 900 sec
G: 14 x 900
B: 16 x 900
L: 13 x 900
Total Exposure time: 14.75 hours
Image Radius: 22 arc-minutes

Processing Tools:
1.    Commercial: PixInsight, Topaz (Studio2), Photo Director 365
2.    Pixinsight Addons: NoiseXTerminator, BlurXTerminator, StarXTerminator
3.    My Scripts: NB_Assistant, AC_Restar, Subframe Weighting Tool (Excel w/ J. Hunt), ColorTweaker

Target Description:
Arp 295, two interacting galaxies with a bridge between and anti-tails streaming away. These extra-galactic features consist of stars and gas pulled from the galaxies by a close gravitational encounter. The total span of the features captured in this image is about 749,000 ly! The bridge has bluer patches toward the lower galaxy, and similar blue patches occur above the upper galaxy (PGC72137). Those are regions of star formation activated by the gravitational distortions. The lower galaxy (PGC72155) also has a star-formation region activated in its strange tail, streaming toward the right.

This interaction is faint, and this data set has revealed it as well or better than any other I have found; even an old Palomar image barely reveals the bridge between the two galaxies. The excellent data, combined with modern AI image-processing tools, allows this level of detail that has largely been hidden until now.

Processing Description:
The processing goal was a sharp rendering of the available details. We now know that the first step in achieving that goal is removing the stars…so I did so as the final step in the PixInsight pre-processing step before invoking tools in the Topaz arsenal. Then, back to PI to replace the stars using AC_Restar (a script I wrote to correctly pick up and transfer stars from a primitive RGB image into the refined colors and intensities of the final image). And voila!

Note that, under the optimal skies of N. Chile, this deep image required only on the order of 4 hours of each channel LRGB. Under the light-polluted, none mountain-peak sites that many of us inhabit, we probably top out in what we can capture at notably less than this level of exposure.

Statistics:
Distance: 0.3B ly
Apparent Magnitude: 14.5
Pixel Span at Target: 0.7 quadrillion km

Alex Woronow