NGC 7727: 1 Spiral + 1 Spiral = an Elliptical Galaxy(AKA, Arp 222)
OTA: CDK24 f/6.5
Camera: Moravian 61000Pro
Observatory: Heaven's Mirror
Date of Capture: up to Dec '23
Date of Processing: Dec '23
Exposures:
R: 21 x 900 sec
G: 19 x 900
B: 16 x 900
L: 19 x 900
Total Exposure time: 15.75 hours
Image Width: 28.5 arc-minutes
Processing Tools:
1. Commercial: PixInsight, Topaz (Studio2, Photo AI2), 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:
NGC 7727 is interpreted as the ongoing merger of two spiral galaxies that began about 1 billion years ago. During such a merger, it is unlikely that any stars will collide due to the great distances between these "small" objects. Still, interstellar clouds may well collide at very high velocities. Such cloud-cloud collisions will spawn shock waves that compress the gasses and ignite star formation. Unfortunately, this pair of galaxies did not have extensive gas clouds, depriving us of a spectacular show.
However, a different perspective appears in this image. Apparently, the two cores of the galaxies have not yet merged, as shown here in the Image labled "Original" at the right . Those cores both have massive black holes that direct the motions of stars around them. This very interesting =11.0ptphenomenon is shown in a video posted here:
https://youtu.be/HnHZY9Py51I.
Processing Description:
The subframes were criss-crossed by an abundance of satellite trails. If they transected the galaxy, I tossed the sub; otherwise, it was used, and I dropped the final background low enough to suppress them but keep the faint outer galaxy.
Statistics:
Distance: 75M ly
Apparent Magnitude: 11.5
Average Surface Magnitude: 24
Pixel Span at Target: 1.4E16 km
Alex Woronow 
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