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NGC1369 & NGC3166

Classification: Sprial Galaxy, NGC3169 / H4-1 / UGC5525
Constellation: Sextans (SEX)
Object Location: Ra 10h 15m 03s Dec +03° 23’17” (current)
Size & Distance: 4.2 x 2.9 Apx 75 Million light years.

Date & Location: 04-18-2015 Little Blair Valley, CA.
Exposure: LRGB; 120, 45, 45, 45, All 15min. (bin 1x1)
Optics: Telescope Engineering Company APO180FL @ f/7.36 using an Astro-Physics 160FF, F/L 1325mm.
Mount: Astro-Physics 1200 GTO / ATS 10x36 pier.
Camera: FLI-MLx694 @-20c / CFW2-7 / FLI-Atlas focuser / Guided by SBIG ST-I / w OAG.
Filters: Astrodon G2 LRGB
Software: MaxImDL 6.08, Photoshop CS5, CCDStack 2.82, Topaz Labs.

Notes: Sky conditions: Very poor seeing, Light wind, Temp low 60’s
Cropped Image Field of view is 31 x 22.5 arcmin.
Field of view orientation; NGC3169(L) NGC3166(R), NGC3165(LoR), and a few PGC galaxies.

NGC 3169 is a spiral galaxy about 75 million light years away in the constellation Sextans. It has the morphological classification SA(s)a pec, which indicates this is a pure, unbarred spiral galaxy with tightly-wound arms and peculiar features. There is an asymmetrical spiral arm and an extended halo around the galaxy.

NGC 3169 is located in close physical proximity to NGC 3166, and the two have an estimated separation of around 160 kly (50 kpc). Their interaction is creating a gravitational distortion that has left the disk of NGC 3166 warped. Combined with NGC 3156, ( not in FOV) the three galaxies form a small group within the larger Leo 1 group. The three are embedded within an extended ring of neutral hydrogen that is centered on NGC 3169.

This is a LINER 2 galaxy that displays an extended emission of X-rays in the region of the nucleus.. A hard X-ray source at the center most likely indicates an active galactic nucleus.. The stellar population in the nucleus, and a ring at an angular radius of 6″, shows an age of only one billion years and is generally younger than the surrounding stellar population. This suggests that a burst of star formation took place in the nucleus roughly one billion years ago.

In 1984, a Type II-L supernova was discovered in this galaxy. Designated 1984E. A second supernova was discovered in 2003; this time of type 1a. It was designated SN 2003 cg and reached peak magnitude 15.94.