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View Full Version : Object of the Week November 12, 2017- IC 2431 A Quad Merger



Jimi Lowrey
November 14th, 2017, 04:03 PM
IC 2431

Cancer

RA
09 04 34
DEC
+14 35 46

MAG 14.6 B

Type Quad Galaxy Merger

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This object I picked from my collection and list of triple galaxy mergers. IC 2431 is listed as a Quad system in NED and looks to be a really interesting cosmic crash! I have not observed it yet but it is high up on my list to observe. I usually do not list a OOTW unless I have tried it so it will be very interesting to here your observations of this Quad Crash.

2803

Sorry for the brief OOTW I have just got out of the hospital and am feeling a little under the weather. I will post more information on IC 2431 at a later date.

As always, give it a go and let us know

Steve Gottlieb
November 15th, 2017, 04:31 AM
Actually, Jimi and I took a look at this interacting system back in 2012. It was on my observing list because I was intrigued by Vorontsov-Velyaminov's nickname. In his 1977 "Atlas of Interacting Galaxies part II and the concept of fragmentation of Galaxies", V-V noted " 'Browning'. Three?" The nickname "Browning" likely refers to a Browning pistol, which it sort of resembles in his Atlas image.

48" (2/21/12): at 488x this compact 25" quartet resolved into a trio of adjacent, extremely small "knots" (galaxies) each ~8" diameter, within a common halo. One or two seem to have stellar nuclei including the knot on the south side, which corresponds with SDSS J090434.82+143536.3 = PGC 200246 (V = 15.7). The other two knots are very close west and northwest (PGC 200245). A mag 12 star is 1.7' NNE. The seeing was fairly poor at the time of the observation, so I needed to wait for steady moments.

Howard B
November 15th, 2017, 05:04 PM
Hope you're starting to feel better Jimi, and will be back to full strength soon.

I don't have an observation of IC 2431 yet, but it's now on my list.

Uwe Glahn
November 17th, 2017, 09:37 PM
Nice object Jimi. I visited the galaxy 4 years ago under normal transparency and soso seeing conditions. My first thought was "looks like a Burger". The knotty structure was immediately visible but the separation of the knots were difficult. I noted the NW ejection as most difficult detail. The longer NW site was the most easiest detail with two knots on each end.

27", 586x, NELM 6m5+, Seeing III
2804

Bertrand Laville
November 19th, 2017, 09:30 AM
Hi All,

Here are my observation and notes of 2017 11 17 at OBP http://www.obs-bp.net/

With 25" Obsession and 519x, the fact that IC 2431 is composed of several object is obvious, but analysis is difficult without the help of SDSS image.
Once orientation is stored in mind, and position of components well memorized, the four galaxies are separated with adverted vision, but with difficulties.

2805

Main component, UGC 4756A is the most luminuous, very elongated, a/b ~ 4 or 5, with a central core samely elongated, but a bit deplaced toward the Nord East. Not nucleus seen.

PGC 0200246 is the second more luminous, with a nucleus glimpsed 25% of the time.
PGC 0200247 has neither gradient nor nucleus, and very hazy limits.
PGC 0200245 is a very little round bowl, well separated from the main body.Nucleus is glimsed 10% of the time.

All object are embedded in a light glow.

Clear skies
Bertrand