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Ivan Maly
October 16th, 2020, 10:23 PM
With the recent (probably last for the year) trip to my 4800 ft, Bortle 2.5 site, I have finished my survey of all objects from the Arp atlas of peculiar galaxies. I started to work on the list systematically in 2017, when I had only about 70 objects seen during my previous exploits. In the beginning, it was done with my old 16", and later with either the club observatory's or, mostly, my own transportable 20. There was no object that completely eluded me in the 16, although later I encountered a few that needed all that I could through at them with the 20 under my darkest skies. For the most part, just detecting the objects was not the goal - I wanted to see structural features, even if they were not always the ones that earned these galaxies their place in the Arp atlas. Below are a few sketches from my recent outing (20", 360x, SQM 21.7). Do we have any other observers here who have either completed the list or are pursuing it?

4040
Arp 164 (NGC 455, Psc)

4041
Arp 121 (MCG-1-3-51/52, Cet)

4042
Arp 100 (IC 18-19, Cet)

Ciel Extreme
October 17th, 2020, 02:19 AM
Congratulations on a terrific accomplishment! That catalogue is not for the faint of heart. I’ve not gone after Arps in any systematic way over the years but I’ve probably tracked down 150 or so... doubt very much if I’ll ever do what you’ve done; my observing circumstances in my backyard while tolerable are hardly deep-sky friendly. The sketches are great, BTW!

Clear Skies
October 17th, 2020, 09:28 AM
Congratulations for your awesome accomplishment, Ivan! Not just for observing the Arps, but even more so for focussing on what makes an Arp, an Arp!

lamperti
October 17th, 2020, 12:28 PM
Ivan,
Great example of perseverance and an excellent eye for detail. I wish I had your young eyes!
Have you considered writing an article for S & T? Many people not on this forum would appreciate reading it.
Al

Ivan Maly
October 18th, 2020, 01:16 AM
Thank you, gentlemen. Al, that's an interesting idea.

morsie
October 20th, 2020, 09:12 PM
Ivan,
A great accomplishment! The only focused ARP exercise I've done is related to the AL's program. I've logged 182. You may inspire me to pick up on this again.

akarsh
October 27th, 2020, 06:34 AM
This is an excellent accomplishment! I do plan to go after the Arps systematically some day in the distant future. But before that, I have a much humbler list to finish, and that's the 100 Hicksons.

Clear Skies!
Akarsh

cloudbuster
March 23rd, 2021, 03:39 PM
Hello Ivan, sorry for not have noticed this topic before. Congratulations with your wonderful accomplishment! Did you also sketch all of the objects (or intend to)? I have started a similar project last year and I'm happy to read that all Arps can be seen with a "mere" 16 inch (my largest instrument). I have indeed noticed that a dark sky is an absolute must to achieve this goal and to be able to (start) seeing details in these fascinating galaxies.

Regards, Martijn

Raul Leon
March 23rd, 2021, 08:06 PM
Exceptional, congratulations! I just saw Arp 321 last weekend, very cool!!

j.gardavsky
March 23rd, 2021, 08:40 PM
Congratulations Ivan!

This is a fantastic accomplishment, incredible, and also because the Arps are those peculiar galaxies.

Your observing skills, and determination is what counts,
Jiri

FaintFuzzies
March 24th, 2021, 03:41 PM
Congrats Ivan for completing the Arp list! Not an easy task.

KidOrion
March 25th, 2021, 12:16 AM
Great work, Ivan! I'm planning on doing the AL's version of the Arp list first, then gradually adding the remainder as I can.

I second the suggestion about writing an article for S & T. They're always looking for writers and topics, so I'm sure they'd be appreciative.

eyeoftexas
March 25th, 2021, 03:22 PM
Congratulations! Truly an outstanding achievement.

Ivan Maly
March 25th, 2021, 06:04 PM
I thank all who have responded for the kind comments. It was interesting to learn about others' exploits with this list. Did I sketch all the Arps? No. Do I intend to? I can only say that it would surely be nice. An S&T article is in the works!