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Hickson 44 in the haze


Nyctimene

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Despite clear blue skies during the days here in SW Germany, transparency has decreased steadily in the nights, resulting in unusual low values of NELM (around 4.8 mag) and SQM-L (20.5). Meteoblue indicated a higher level of PM 2.5 and PM 10 particles (not Sahara dust). So my expectations weren't too high, when I took out the 18" f/4.5 Obsession yesterday evening. But I had fixed some problems with the 10x60 Baader finder and swapped the SkySurfer III against a Rigel Quikfinder, that I wanted to align. Started with Gamma Leonis, Algieba, which showed at 164x mag (12.5 mmf Docter) as a nicely split double (4.8"). The seeing was above average. The Leo triplet M 65/66 and 3628, fitting completely in the 1° field of the Maxvision 24mmf/82°, showed less contrast as usual, especially the fainter 3628. Over to Hickson 44 = Arp 316, nicely placed and easy to find between Algieba and northern Adhafera (Zeta Leonis). This group of four is the brightest member of the 100 Hickson groups. Three of it's members, NGC 3187, 3190 and 3193 are interacting galaxies. Two of them were easily visible at 164x. 3193 (11.0 mag) showed as a round galaxy with a bright central region, just S of a 9 mag star. Close by in the same field of view was 3190 (10.9 mag), in contrast to the former a 3:1 spindle with brighter core, E-W elongated. SW was the 12.1 mag 3185 (not interacting), considerably fainter, round, and diffuse, but still to hold in direct vision. The fourth member, 13.3 mag 3187, could not be made out, indicating the low transparency (usually I can get down to 15.5 mag for the average E galaxy without problems). So I finished the session after one hour at 21h15 CET. The Quikfinder/Baader finder combo had worked well together, and I rewarded myself with an excellent B.Nardini Grappa Riserva (60° proof).

The three brighter members of the Hickson 44 group should be accessible with the average 8" dob under good conditions, so give it a go, and let us know

Attached a drawing with an 17.5" (from the net); 3185 is top left, followed to the right by 3190 and 3193 (close to the star):

Hickson 44 with 444mm Dob., 14/04/2018

Thanks for reading

Stephan

Edited by Nyctimene
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Well done for giving it a go despite the poor transparency.

It's the same here but I took my 8 inch out for a run and looked at m81 and m82. They were right overhead so that helped. I could see to mag 14.1 with the 8 inch which was impressive given the conditions.

Mark

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Spotted Hickson 44 (it's two brightest members) again last evening with the mighty little Skywatcher Heritage 130 P Flextube. Under NELM 4.6 skies, 3193, close to the 9 mag star, showed as a round, faint haze, but almost constantly visible with averted vision. The spindle of 3190 was also visible with AV (83x mag). So I had a look at Arp 94, just E of Algieba, and found gx 3226 (11.4 mag) and 3227 (10.4 mag) as an oblong agglomeration, not separated under the given viewing conditions, but well visible with AV. The two Leo triplets followed; 3628 showed it's extended structure, but without details. Finished after 1 hour at 23.00 CEST.

Stephan

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On 25/03/2022 at 09:03, Nyctimene said:

… and I rewarded myself with an excellent B.Nardini Grappa Riserva (60° proof). …

What does that translate to in terms of _true_ Field of View 🙃?

Seriously though very interesting and added to my next session!

Cheers, Magnus

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10 hours ago, Captain Scarlet said:

What does that translate to in terms of _true_ Field of View 🙃?

Well, it's a bit like observing with a Zoom eyepiece. At the default setting, with the longest focal length, there is a certain True Field of View and an according Apparent Field of View. The next step (=first drink) will show you a larger AFoV, but in reality, the TFoV has narrowed down. This divergence will increase with  the next steps (=drinks, not recommended with a 60°!). OK; with higher magnifications you will be able to see smaller and fainter objects - but the general brightness of views will be dimmer...... and so on, until clouds are rolling in 😉

Stephan

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  • 2 weeks later...

I've become quite the fan of Hickson groups and have had great pleasure observing them. Keep trying for 44 as it's immensely rewarding when you get the right conditions. 
My view of it two weeks ago was exactly like the drawing you shared. 

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