Vorontsov-Velyaminov interacting galaxies

[Mike JW]

I was pleased to pick up the loop - obviously not as sharp as decent images but the shot gives a feel what is going on with this pair.

Mike

[Mike JW]

VV 697 in Pegasus is a lovely example of the classification; NNN = separated triples. All three galaxies (mag 15/16) are likely to be a true group as they are all about 850 million lyrs away. The top two appear to be linked by a bridge of stairs, indicating an interaction. Certainly the left galaxy is somewhat disrupted.

[Martin Meredith]

That's a great find. The middle galaxy looks like it has been through the wars.

I was also looking at a few VVs last night in Pegasus. I spotted this one thinking that the surrounding galaxies would make a good setting, and indeed there is a lot going on here, apart form the relatively rich star field. Not an NGC or IC in sight, but a variety of UGCs and fainter on display. VV 1955 is the indicated pair (SW of the label) at around 323 MLyr. The other galaxies are at a similar distance, so this looks to be a genuine grouping. I imagine it has a WBL listing too but haven't yet tracked it down.

There are a lot of close (optical?) doubles in the centre of the image making it look like a stacking error, but they are genuine.

[Mike JW]

A great view. I have not visited this area - now on the list. Nice sharp diffraction spikes. So much to see in this shot.

Mike

[Bill S]

Plenty to see in that shot, Martin.  Yet another area to have a look for.

Bill

[Mike JW]

Last night I took a look at VV 1955. What intrigues me is it would appear to be a pair of elliptical galaxies which are very close to each other and most likely interacting, yet the VV catalogue gives a classification as NNNP; a triple with a tight pair. The question is where is the third member or is one of the ellipticals really two galaxies? Hence my desire for a closer look.

The zoomed in shot below indicates some possible disruption to the southern elliptical. Its core is elongated. I can not see any signs of third galaxy - mystified!!!

Mike

[Mike JW]

VV 1947 in Aquarius is also known as IC 5241. It lies about 370 million lyrs away and is obviously messed up, hence the classification of Scd pec. Colour images show much blue suggesting plenty of star formation. The VV classification is 'N' = three or more galaxies and at first glance it would be tempting to agree with this, as there are clear bright nucleus like areas. However these bright spots would appear to be star forming regions. Aladin does show the presence of a second galaxy just north of the main core but not picked up in my shot, but no other galaxies indicated - certainly not the 3+ as suggested by VV

Mike

[Mike JW]

On the same night I visited VV 1977 in Pisces which is a pair in contact - no data found on this one. However the nearby pair of UGC galaxies made for an interesting viewing. They are likely to be companions as they are only about 5 million lyrs apart. Both are spirals. Also note the quasar at the top.

Mike

[Martin Meredith]

I note the early evening observation times of these shots -- one of the advantages of late November in the UK I suppose!

VV 1947 is suggestive of having an edge-on spiral to the upper right of the core. Must be fun trying to sort that one out. It is reminiscent of some of the overlapping galaxies -- I'll check to see if it is mentioned in that catalogue.

The brighter member of VV 1977 seems to have a double core, but this might be an illusion. Its a good example of visiting one object but finding other interesting galaxies in the field. 

Martin

[Mike JW]

Hi Martin,

The brighter blob - upper right does actually have a PGC number. It was still twilight when I started my recent two sessions and finished by 7pm - very civilised. Although I now have Christmas lights adding to the LP from surrounding houses.

Mike

[Mike JW]

VV 699 (and NGC 1723)

This area was Galaxy of the Month back in December 2021 - see https://www.webbdeepsky.com/galaxies/2021/ - excellent summary of the area.

NGC 1723 (at the top) - SB(r)a - pec. Such a clear inner ring with the distinct arms coming off the ends of the bar.

VV 699  - the three galaxies at the bottom. The right hand galaxy, NGC 1721 is also a ring galaxy but this time it is an outer ring - (R)SAB(s) - pec

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Mike

[Martin Meredith]

Thanks for reminding me about this. Surely one of the most interesting fields for small sensors? Here's my slightly wider view from 2020 which also incorporates a near integral-sign galaxy (top right). This is PGC 16507, type SBc(bar). Actually, there are quite a few fainter galaxies in the image, mainly edge-on.

 

A highly-stretched close up of NGC 1723 (at the base in the above shot but oriented correctly below) suggests very unusual outer arms that are straight and tangent to the galaxy itself. I wasn't sure whether these were artefactual (no time to investigate further as yet) but I can see them on your shot too. [ignore the pesky tooltip -- I'm still working on them]

Martin

[Mike JW]

As always Martin, the wider field of view gives context, added interest and beauty. On high resolution images the arms are straight - unusual? Line of sight?

Mike

[AstroKeith]

If any of you VV observers use a Nexus DSC, I attach a Nexus dBase of the VV catalogue. I produced it last year for a friend (Serge at AstroDevices has given me the wherewithal to create Nexus databases but its not easy!)

 

VV.db

[Mike JW]

VV 454 (NGC 4137) in CVn presents an interesting challenge. A lovely open spiral  - SBc with a spiral on its arm. However the VV catalogue classifies it as MM, meaning two satellites on its spiral arms. One is very obvious so where is the other?

 

Zoomed it shot and labelled according to NED, shows the other galaxy on the spiral arm as well as a possible third galaxy but not redshift data available. for these two galaxies.  NGC 4137 is 503 million lyrs away but the 17.5 galaxy is 497 million lyrs away - thus not really on the arm - line of sight.

Mike

[Martin Meredith]

Though I wonder what the confidence intervals are on those distances? They seem close enough for the system to be interacting, and there does appear to be a faint bridge between the two, but that might just be wishful thinking...

 

[Mike JW]

I came across VV 968 in Pisces. It is designated as NN = 3+ galaxies but disrupted. The two close galaxies in professional images hint at the galaxies disrupting each other. The third member is off to the left. They all have very similar redshift values.

Just above the middle galaxy is a small fuzz patch - this galaxy is much further out.

The indicated quasar is 3+ billion lyrs away but I doubt it is mag 21: maybe mag 19/20

Mike

 

[Martin Meredith]

Its a while since we had a VV entry, so here's one: VV 179 in Coma

The VV pair (or triplet) designates the two obvious ellipticals lined up vertically near the base of the image. The starlike object to the right of the upper galaxy is also a suspected elliptical with a similar distance estimate.

What makes the field compelling is the number of other 'major' galaxies present (although they are nearly all ellipticals), as well as a flat galaxy catalogue member and a host of faint galaxies. This north-up annotated shot shows some of them. The PGC galaxy labelled has a B-band magnitude of 20.0 and I can just about make out one at mag 20.6 at around 6.5 billion light years distance, so it must have been a reasonable night for seeing and transparency. All in all an interesting part of the sky to visit.

 

 

 

[Martin Meredith]

Just catching up on other observations from April...

Here's a 5-minute-ish capture of a field in Coma containing VV 61 and much else besides.

VV61 is the pair type Sab NGC 4098 and a mag 15 PGC companion, at around 360 million light-years. There are 5 other NGC galaxies in the field. NGC 4092 is a nearly face-on Sab type at 326 MLyrs, so perhaps part of the grouping. NGC 4093 is an elliptical, also at around 344 MLyrs, as is the compact elliptical NGC 4095 (346 MLyrs). The pair NGC 4091 and 4089 are also listed as being in the 350-370 MLyr range.

This latter pair is also a member of the catalog of overlapping galaxies, important astrophysically as they allow estimates of the foreground galaxy's structure to be determined based on the appearance of the background galaxy.

Completing the interest in this rather small field (we're looking at around 15 x 15 arc mins) is a Palomar Compact Group which is listed as having 4 members, though there are at least 6 galaxies in the general area circled. The brightest of the group is mag 17.8. I don't have a distance estimate for the PCG group but I suspect it is rather further away than the NGC grouping.

The rather unprepossessing VV 62 is just outside the field for those with larger sensors.

cheers

Martin