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View Full Version : Object of the Week October 7, 2012 The TAFFY II Galaxies UGC 816,UGC 813



Jimi Lowrey
October 7th, 2012, 08:24 PM
UGC 816

UGC 813

Taffy II galaxies AKA VV 769

Andromeda

RA
01 16 20

DEC
+46 44 60

MAG 14.2 P and 14.8 P

TYPE S in interaction

Last week while I was doing research on the Taffy galaxies (UGC 12914/5) I came across the 2002 AJ paper A Second Taffy pair by JJ Condon. This caught my eye and after seeing many referrals to this paper about the Taffies UGC 12914/5 I read it. I must say I was blown away by how much the Taffy II are morphologically like the Taffy I galaxies. They both have a strong molecular bridge the is caused by a long time of interaction between the two.
NRAO Image
311

I can't wait to try this pair this dark period! I wonder how much of the bridge between the two will be able to be seen? I look forward to hearing your observations of this odd pair that Arp did not put in his catalog of peculiar galaxies.
SDSS image
312

The other bright galaxy is CGCG 515-11 MAG 15.1 but is not part of the interaction. If you would look at the NRAO image above and the DSS image below 2.6' West North West of UGC 816 is a faint dwarf galaxy that is interacting with the two larger galaxies and is part of the system. From the SDSS photometry this little dwarf is approximately 17.1 V mag and should be able to be seen by many of the telescopes in this forum under a dark sky. If you are able to observe this little dwarf I am sure you will be in the company of very few visual observers,
DSS image
313

At the time I write this I know of no visual observations of this Little dwarf that is part of the TAFFY II interaction so be sure the next time you are under a clear dark sky to,


"GIVE IT A GO AND LET US KNOW"

GOOD LUCK AND GREAT VIEWING!

KidOrion
October 7th, 2012, 11:13 PM
All this taffy's going to be bad for my scope's teeth!

FaintFuzzies
October 8th, 2012, 03:31 PM
Thanks Jimi, I'll make a run for this dwarf the next time I make a run to Shot Rock, hopefully this Saturday.

Anyhow, I've observed this "trio" last year. http://faintfuzzies.com/OR-Dec172011-BC.html 4th one down.



MCG+8-3-11 trio RA: 01 16 11 Dec: +46 44 05

22” f/4 (230 and 383x)

MCG+8-3-11 01 16 04.5 +46 43 50 0.9x0.4’ 15.1) – Considerably faint 5:2 elongated glow. Even surface brightness. With averted vision, very faint short extension on each end are detected PA = 30 and 0.4’ long.

UGC 813 (01 16 16.5 +46 44 27 1.2x0.5’ 14.8p) – Considerably faint 2:1 glow with a brighter center. PA = 120 and 0.3’ long.

UGC 816 (01 16 20.8 +46 44 51 1.9x0.9’ 14.2p) – Considerably bright glow with a much brighter center. With averted vision, very faint spiral arms are intermittently detected.

MCG+8-3-11 trio RA: 01 16 11 Dec: +46 44 05

Jimi Lowrey
October 8th, 2012, 10:24 PM
Alvin Be sure to let us know about the dwarf. I would like to hear how you do even if its a negative observation.

RolandosCY
October 10th, 2012, 08:37 AM
In between the strong storms of the last few days we did manage a couple of hours last night at a rural site (Mazotos beach, SQM 20.9). I did manage to spot the two brighter galaxies but the seeing was continuously changing and could barely distinguish the two components at 294X. Most of the time it seemed they were connected at one end, sort of like a mussel. Did not manage to see the little guy, but if it clears by Sunday I will again have a go at a high altitude site...

lamperti
October 13th, 2012, 12:53 PM
Saw these two last night but the sky did not allow me to see a gap between them (SQM=20.4) and average seeing. UGC816 was definitely the brighter of the two. BTW: Uranometria Field Guide lists the magnitudes as being in the high 13's.
Al
22"f4.8 Obession U.C.

Steve Gottlieb
October 15th, 2012, 04:24 PM
I also took a look Saturday night at a local site (Lake Sonoma), though transparency was noticeably down due to high humidity. The trio was easily visible in my 24", though no sign of the dwarf. Observation was at 375x:

UGC 816: fairly faint to moderately bright, elongated 5:2 ~N-S, ~0.6'x0.25', brighter core. Slightly brighter and larger of a close pair with UGC 813 just 50" SW. CGCG 551-011 lies 3' SW forming the isolated triplet KTG 4.

UGC 813: fairly faint, elongated 5:2 WNW-ESE, 0.5'x0.2', brighter nucleus. This galaxy is the western member of an interacting "Taffy" pair with UGC 816 just 50" NE.

CGCG 551-011: faint to fairly faint, small, elongated 2:1 SSW-NNE, 0.4'x0.2', fairly high surface brightness.

Jimi Lowrey
October 15th, 2012, 05:19 PM
Last Tuesday night Jim Chandler and I tried this pair on a night of fair transparency and below average seeing.

UGC 816 was brighter than UGC 813 and with the 12MM TMB Supermono at 407X during moments of good seeing the faint bridge between UGC 816 to UGC 813 would pop in. The bridge to my eye would not quiet go all the way to UGC 813 but faded out 3/4 of the way to it. I could not hold this with AV it would only momentarily pop in and out of view with the seeing.

The dwarf galaxy with the 12MM TMB was direct vision and in moments of good seeing would extend looking like a 1/4 facing spiral with a brighter core. I was surprised at how dim the star it was by was on this night. You have to look in just the right spot to see the dwarf as it is small and dose not jump out at you in the crowded star field and at low power looks like a fuzzy star with a spike on one side.

FaintFuzzies
October 15th, 2012, 07:23 PM
I did make a run for the dwarf galaxy. I didn't see it, but do see the star just off the SW edge.

That was under NELM 7.0 skies with a 22" scope. Used 6mm and 4mm ZAO-II with and without the TMB 1.8x ED Barlow.