ARP GALAXIES

[roelb]

My latest EAA on Arp 285:

6 SE @ f/5 with ASI290MM

Bortle 7

39 x 8 s

 

[Mike JW]

Great to see you got the three bright spots in NGC 2856.

Mike

[catburglar]

I had another go at Arp 285 tonight to see if I could get any hint of the jet or tidal tail- but still no joy for me. It was a little less breezy than previous attempts, so I could get 20second exposures before field rotation became an issue. The moon, although nearly full, was still low and Arp 285 almost at the zenith for me, so not quite ideal, but pretty close. But...I still didn't get it...so maybe wait another week or so 'til the moon is well away.

[PatG]

A poor attempt by comparison to the other images on this thread but, this is a capture from last night of Arp 104 / NGC 5216  & 5218 or Keenans System at circa 185 MLY.

May not be much to look at but rewarding none the less!!

 

[Mike JW]

Hi Pat, we all have to start somewhere. You should see some of my early attempts - straight to the bin.

Mike

[Mike JW]

Arp 285 - much better conditions last night. The shot below: reduced the noise right down to leave the tidal jet/tail clearly visible but faint. If I adjust the settings differently I could not get any hint of the tidal stream between the two galaxies so I reckon it is beyond my set up and unless I started doing long exposures but I shall not go there.

Mike

[Mike JW]

Arp 233, also known as UGC 5720. It also has the designation of VV 1370 (N?). Arp thought it was a galaxy with the appearance of fission. The VV classification suggests that there could be a tight group of galaxies. In colour images it is very blue, indicating starburst activity.; is this because it is actually a group but if it is just one galaxy then it must have interreacted with some other galaxy, but what is the candidate for this interaction? NED classifies it as Im Pec = dwarf galaxy that is messed up.

Mike

[PatG]

Hi Bill

Great capture., the bridge is definitely discernible. I had a go at Arp 104 / Keenan's System this evening. Here is my capture for comparison.

Using a smaller scope a 100mm F8 refractor with circa 0.5 focal reduction and lodestar mono x 2 also - so a much wider field but no sign of the bridge!

Pat

 

[AKB]

Bit of an Arp-fest last night, taking in some of the vistas in Ursa Major and Canes Venatici:

• Arp 18
• Arp 27
• Arp 269
• Arp 281
• Arp 299

I can only find 269 previously posted on this thread (twice by @Mike JW) here:

• https://stargazerslounge.com/topic/351721-arp-galaxies/#comment-3882086
• https://stargazerslounge.com/topic/351721-arp-galaxies/page/4/#comment-4042150

so I'll just add my images here, and not repeat the discussion.  The widefield gives some nice context, but the narrow is pretty similar to previous postings.

For the others, I'll add separate posts once I've absorbed some of the information and background on them.

Tony

 

 

 

Edited March 26, 2022 by AKB

[AKB]

Arp 18

So much going on here.  Arp 18 turns out to be NGC 4088, VV 357, and in the wider field we also have VV 1504 and NGC 4085, plus a host of more distant galaxies.

The close-up of NGC 4088 shows why it is described as "spiral with detached segments".   The catalogue shows it to be 40 Mly distant but 'nearby' galaxy PGC 38369 is much further away at 845 Mly.  Even more distant are PGC 3411579  (mag 18, 1045 Mly) and PGC 3411583 (mag 18.7, 2663 Mly).

 

NGC 4085 and vicinity

62 Mly away, classified as SABc(bar) is magnitude 12, and easily outshone by the magnitude 8/9/10 stars in the same field.  PGC 3411573 is aroung 3.5 Gly away.

 

VV 1504

This galaxy cluster is about  900 Mly distant, but PGC 3411607 is around 3.3 Gly and magnitude 19.

 

All in all, another splendid area of sky (but there again, what isn't?)

 

Tony

 

 

 

   

 

   

Edited March 26, 2022 by AKB

[Mike JW]

Hi Tony,

So much of interest that I have been back to your post three times now just to absorb the features - housework has been abandoned!!!

Last night I decided to visit Arp 18.

In addition to Tony's notes - it is a grand design spiral. Arp refers to a detached segment which I presume is the bit at the top. Classified as SAB(rs)bc H11 = intermediate spiral with fairly tight arms, no ring and buzzing with star formation. It belongs to the M109 group of galaxies.

VV 1504 intrigued me because it is classified as a distant pair with a bridge, indicating there is an interaction going on. Could I pick up the bridge? Aladin image for comparison. Maybe I got a hint??? Need to do a longer exposure.

 

Mike

[Bill S]

Prompted by the recent views views of Arp 82 posted by AKB towards the current end of this thread https://stargazerslounge.com/topic/349834-cancer-arp-82-shk-185-hickson-37/?do=findComment&comment=4226745 I had another look at this fine specimen last night.

 

Rather a lot of subs because I left it running while I popped into the lounge to talk to my wife!

Edited March 27, 2022 by Bill S

[Mike JW]

A good result. My image shows no more detail than yours but then mine is not for 18 mins.

Mike

[AKB]

Arp 27

Another one from my recent Arp-fest.  This reminded me of Arp 1.

NGC 3631 is described as "spiral with one heavy arm" and Arp's notes include the comment "Note straight arms, absorbtion tube crossing from inside to outside of S arm."

Not quite sure what I am looking for here, so if someone can point out or explain further, that would be great.

I can only find two other galaxies in the wider field with discernable shapes:

• PGC 34523 – mag 15.6, type Sab(mult), 712 Mly
• CGCG268-023 – mag 14.7, type E(compact), 489 Mly, with two other galaxies of similar distance in the zoomed field and also a couple of quasars.

What's not to like?

 

 

 

   

 

   

[Mike JW]

I too recently took a look at Arp 27.

My suggestion of the features - see below. Open to the idea that the labels are incorrect.

Image processed using the latest Jocular version - definitely helps to bring out features as well as the resolution power of my Dob.

Mike

[AKB]

17 hours ago, Mike JW said:

My suggestion of the features

Thanks for that.  Makes sense to me.

Should I be worried that one of the stars directly below it, and at about 1 o'clock from the little galaxy which is PGC 2432364, has apparently moved a bit to the right ... ?

[Mike JW]

Hi Tony, how intriguing - you also have a couple of other fuzz spots close to the galaxy - fleet of alien spacecraft??

Aladin view does not show the two fuzz spots.

Mike

[Mike JW]

On 20/03/2022 at 14:04, PatG said:

A poor attempt by comparison to the other images on this thread but, this is a capture from last night of Arp 104 / NGC 5216  & 5218 or Keenans System at circa 185 MLY

Pat - the 22,000 light year bridge between the two galaxies is a hard target. NGC 5218 (at the top) has a counter tail (heading North, up) - just got a hint of it. NGC 5216 also has a counter tail, curving down and to the right - reasonably clear in my shot. These two galaxies are seriously interacting and giving each other a hard time!

Here is my recent attempt, prompted by your post.

Mike

[roelb]

Imaged Arp 104 "The Keenan's System - Bridge" back in 2020.

Evo 8 @ f/5

ASI533MC-Pro

20 x 45 s

In the inverted image the "Bridge" can be 'hardly' seen.

[AKB]

Arp 214 and friends

Yet another Arp from my recent haul, and, again, so much to see.

The wide-field landscape image covers about one degree across the diagonal.  Before moving on to the narrower labelled eyepiece field, take a moment to spot FGC 1259, the little edge-on spiral at the middle of the bottom edge of the image.  This is mag 17 at a distance of 483 Mly.

For the larger objects, we have:

• Arp 214 / VV 1449 / NGC 3718
• NGC 3729
• Arp 322 / VV 150 / Hickson 56 / UGC 6527

 

Arp 214

Arp noted this as "Barred spiral, sharp nucleus, narrow absorption lanes through the centre" which is a pretty good summary.  This image here compares favourably with that of Robert Gendler using a 12.5" RC, f9, with 150 minutes of exposure, as shown in the The Arp Atlas of Peculiar Galaxies.  No hint, though, of the faint extended peripheral structure shown in a hand-drawn diagram along side that, which was based on a separate image from a larger scope.

The notes in the atlas say:

• "NGC 3718 is mag 10.7, 9.2' x 4.4', and SB(s)a pec  (Seyfert 2).  It is a LINER (Low-Ionization Nuclear Emission-line Region) galaxy, possibly interacting with NGC 3729, following to the E.  Called a barred spiral, but the bar is an absorption structure, not stars."

 

NGC 3729

Classified as Sa(bar, ring, mult) this is mag 11.5 at a distance of 67 Mly.  It shows really great structure.  The labelled galaxy PGC 3400984 is mag 18 at some 2.2 Gly.

 

Arp 322

Looks like every catalogue wanted to claim this group!  As well as the galaxy chain (left to right A – E, components B,C,& D are Seyfert 2 galaxies), at a distance of about 400 Mly, there's a couple of quasars sitting in there too, apparently.

 

Real value for money, this area.

Tony

 

 

   

 

 

   

 

 

 

 

Edited March 29, 2022 by AKB

[Mike JW]

I too have been going through the UMA Arps in the last few sessions, so great to see your wonderful collection of shots/info. I always get a thrill out of hunting down edge on galaxies; the FGCs. It always gives me a buzz to find the faint ones so your FGC 1259 does it for me!! (must get a life?).

Arp 214  from a few days ago. Tricky to know how best to tweak the sliders to get the best overall view. I have managed to get some detail associated with the curving dust lane (especially on the right). On the right hand side above the curving dust lane is an almost straight dark line (artefact is my first thought) and then on the left side, below the curving dust lane is a dark spot - another artefact. SEE my second shot with red lines indicating these features.

Checking against quality images - they are both real - amazed.

 

 and finally here is the same shot but with different annotations and tweaked differently - some very faint stuff brought out in this shot.

 

Arp 322 - I think I will post my shot of this into the Hickson thread, as Hick 56 with any suitable info.

Mike

[AKB]

Really nice, Mike.  That big aperture is really working hard for you.

[roelb]

Arp 214 from a few days ago.

Evo 8 @ f/5.3

 

[Mike JW]

Hi Roel,

You got the ring structure of 3729 and of course another FGC for me as part of H 56.

Mike

[AKB]

On 28/03/2022 at 23:16, roelb said:

Imaged Arp 104 "The Keenan's System - Bridge" back in 2020.

Had a go at this last night... not observed it previously.

Actually, I had two attempts: one at the start of the session; one towards the end.

• The wide field (1º x 0.76º) captures NGC 5205, and (centre bottom) flat-ish UGC 8491
• Late evening (22:45) clearly shows the bridge, but it's pushing into the noise even at 15 minutes worth
• Early evening  (21:05) the bridge is barely visible after 10 minutes.

I think that the darker sky a bit later makes the main difference here.

I enjoyed giving this a go, so thanks to @roelb for the inspiration.

Tony