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View Full Version : Object of the Week September 10th 2017- IC 1365 Compact Group of Galaxies



Jimi Lowrey
September 11th, 2017, 04:50 AM
IC 1365

Type cD galaxy

Equuleus

RA
21 13 55
Dec
+02 33 53

Mag 14.6

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IC 1365 is listed as the cD galaxy of a compact group in the small constellation Equuleus. It was found by Edward Swift the son of the famous Comet hunter Lewis Swift on September 28 1891 with his fathers 16" Clark refractor at Echo mountain in California. Edward swift is the youngest contributor to the NGC and IC catalog.

Edward and Lewis at the Telescope
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I was recently in the San Francisco bay area visiting Steve Gottlied and he arranged for us to tour the Swift telescope at its home since 1942 at Santa Clara University. I have been wanting to see the 16" Clark for years. We had a wonderful visit with the old scope. It was exciting to me to be so near the telescope that had found so many NGC and IC objects. I was sad to learn that the dome was sealed shut and the scope was inoperable. I hope some day that this historical telescope will be able to see the stars again!

Swift Telescope
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Steve and I with the telescope
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I took a look at this group with Paul and Debbie Alsing's 18" reflector in the wonderful dark skies of the Steen mountains in South East Oregon recently. I was only able to see 3 of the 4 members.

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I took a look tonight with the 48" under very windy conditions. It was hard to split the two galaxies in the middle at 375X. That is why I did not see them with the 18". When I bumped up the power to 610X it was easy to split the pair in the middle. it was a nice view with all of them in a faint halo. The galaxy to the East is the dimmest of the 4. I did get a pop or two of the very faint galaxy that is NW of the center galaxy. The Edge on Galaxy (2MASX J21134684+0233497) west of group was easy to see at all powers.

If you are a fan of compact groups like me be sure to give Edward Swifts IC 1365 group A GO! and be sure to LET US KNOW.

Norman
September 11th, 2017, 03:39 PM
Nice 1 Jimi!

When i saw the jpg of the group first thing i did was smiling :-)

It´s on my list now and so far conditions in one week allow - i´ll give it a try.

CS
Norman

Ciel Extreme
September 18th, 2017, 08:40 AM
I had a look at IC 1365 tonight, though the seeing alternated between bad and terrible and the transparency was average as well (stars naked eye to between +5.6 and +5.8). I wasn’t able to resolve any of the members with my 22" at 303x (451x and the sky glow from a very faint aurora killed contrast). The group looked very much like an S0 galaxy seen edge on, the “bulge” in the middle was the middle N/S pair. The edge-on galaxy to the west I could barely make out... only the core was seen. Interestingly, about a half degree to the SE is another, very similar chain of galaxies, the brightest being IC 1370, discovered by Stephane Javelle in 1891. I had a look but could only see IC 1370, no evidence of the companion galaxies. Both IC 1365 and IC 1370 are about the same distance away (around 650 million light years). I’d be curious to know if this group is resolvable in your 48" as well. 2655

Steve Gottlieb
September 18th, 2017, 07:00 PM
I also took a look at IC 1365 on Saturday night from a local site (Lake Sonoma), north of Santa Rosa under fairly poor transparency. I'm not sure if we had some thin clouds, but the Milky Way was certainly washed out and I suspect there is still smoke around from wildfires in California and Oregon.

Using my 24" at 375x, the main (central) component (IC 1365 NED01) appeared faint, small, slightly elongated ~E-W, 0.4'x0.3', small brighter nucleus. Just at or off the west end [21" between centers] I could resolve a very faint, extremely small glow (IC 1365 NED02), ~6" diameter. The third fainter component at the east end of the halo was difficult to confirm and I'll have to take another look under better conditions. The combined glow of the 2 or 3 components extended at least 0.5' WSW-ENE.

I viewed IC 1370 a couple of years ago in my 24" at a much darker site in the White Mountains (elevation 8600') and described the main galaxy as "faint, very small, round, ~12" in diameter. Forms an extremely close "pair" with a mag 16 star [10" east of center], close to the edge of the small halo! An extremely faint, stellar or nearly stellar object was occasionally glimpsed close to the west. This was probably LEDA 1219013 = 2MASX J21151273+0211354 [24" W], itself a double system, with a B magnitude close to 17.

Jimi Lowrey
September 19th, 2017, 03:11 PM
I took a look at IC1370 last week under not so good transparency. I have viewed it before and found its members much harder to resolve than IC1365. I only could see two members.

Norman
September 22nd, 2017, 08:20 PM
Hi folks,

using my 12" at 170x-290x i saw a weak longish smudge. In one moment one or two flashes occured within but i couldn´t repeat that. Yet i didnt try hard to repeat. No way to separate anything for me. All in all not that easy but still good visible in 12" under good conditions around NELM 6m5 or better. My sky was around NELM 6m8+, Seeing was mediocre to good.

CS
Norman

theritz
September 25th, 2017, 07:41 PM
I collected a few fresh photons for your viewing pleasure.
Nothing much to look at, I know. But since this pic is made of only 5 frames of 180s each I am pretty happy with the result. Also I used freeware to process it (SIRIL and GIMP).
It's in there!

http://theritz.nl/wp-content/uploads/2017/09/IC1365_nebufied_DDP_despeck_highpass.png

Uwe Glahn
October 10th, 2017, 07:53 PM
What a cool object Jimi.
Visited it last new moon and was amazed. Difficult but exiting.

The separation was only possible because of the good seeing conditions and from 586x up. 419x did not show the smaller and stellar like companion. I also tried to go as deep as I could and catches some other companions.

sketch: 27", 586x, NELM 6m5+, seeing II-III
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