Object of the Week, April 1 2018----NGC 3758 "The Smiley Face Galaxy"

[Jimi Lowrey]

NGC 3758/MRK739-- Smiley Face Galaxy AKA The Owl Galaxy

Leo

RA
11 37 25
DEC
+21 29 46

Type Spiral Galaxy with two AGN

Mag V 14.59

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I am filling in for Paul sorry for the late post.

NGC 3758 is a rare type of galaxy merger with two super massive back holes that are dancing around each other in a death spiral. Not many galaxies with dual AGN's (DAGN) are know. I have recently started to collect and observe these rare and most usual type of galaxy and really get a kick out of trying to see the two nuke's in them.

NGC 3758 was found by Ralph Copeland on March 18 1874. Professor Bill Keel gave it the Owl galaxy name in a 1993 article in Mercury magazine.

ngc3758.jpg

I have observed 3758 many times over the years and most recently two nights ago. The conditions that night was seeing 5/10 and transparency 8/10. I always give a chuckle out loud when I see the two bright cores starring back at me. At 610X the DAGN was easily split and seen with direct vision and is surrounded by a small round fuzzy halo.

More info https://www.nasa.gov/mission_pages/s...ack-holes.html


Be sure to check out the Smiley Face galaxy and see if it makes you LOL.

Give it a Go!

[Steve Gottlieb]

Here's the 2011 announcement "Nearby galaxy boasts two monster black holes".

and journal paper "Chandra Discovery of a Binary Active Galactic Nucleus in Mrk 739"

I also observed this galaxy a year ago through Jimi's scope. It's located only ½° southwest of Copeland's Septet (HCG 57)!

At 697x; moderately bright, round, 30" diameter. The two stellar nuclei were cleanly resolved, separated by only 6" E-W. The eastern nucleus seemed slighter brighter or more stellar-like. The western nucleus was quasi-stellar (perhaps a few arseconds diameter).

[Paul Alsing]

[QUOTE=Jimi Lowrey;6534]NGC 3758/MRK739-- Smiley Face Galaxy AKA The Owl Galaxy

Leo

RA
11 37 25
DEC
+21 29 46

Type Spiral Galaxy with two AGN

Mag V 14.59

----------------------------------------------
I am filling in for Paul sorry for the late post.

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My phone's calendar failed me, Jimi, I had no idea that I had missed my turn at bat

Oh, the shame... but you picked a great object, a Home Run! Thanks!

[Jimi Lowrey]

No problem Paul glad I could fill in

[Robin]

Hi Jimi,

I tried this one with my 12" Dobsonian. It was quite a challenge due to bad seeing conditions (clouds dissolved after a shower, but cirrus clouds approaching at the horizon, NELM at zenith was 6.5).
Altogether, I spent 30 minutes at the eyepiece, waiting for brief periods of better seeing like when observing planets. I switched back and forth between 275x and 505x magnification. 505x turned out to be empty magnification. At first, I only saw an elongated and diffuse patch. But again and again I was able to see something shaped like the number "eight", so I couldn't resolve them completely under these conditions. I should definitely try again!

Clear skies

Robin

[Ivan Maly]

Two theoretical notes on this object, since we have no observing weather. First, there is a large tidal tail or loop NE and SW of it, similar in outline to the one in the "Eyes" in Virgo. Most of it is visible in Jimi's image frame, but it can be more noticeable in a wider field. Due to its size I suspect it may be observable. Second, this galaxy, or system, is part of a 400 Mly-distant cluster USGC U404 (NED name), whose 6 other members include the principal galaxies of the Septet and PGC 43877, which lies midway.

[Uwe Glahn]

Very cool object Jimi. I got both cores with the 27-inch despite horrorable conditions (wind, bad seeing and transparency). I add a sketch when I redrawn it.

[Robin]

Hi Jimi,

I tried again this weekend and had better seeing conditions. I had to set my alarm clock to moonset, though. :-)
This time I was able to split the nuclei. I only saw two star-like objects.


Clear skies

Robin