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ZielkeNightsky
sage
Reged: 10/01/06
Posts: 378
Loc: Denmark
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Hi
A few days ago I was observing Zwicky's Triplet / Arp 103 with my setup.
After the observation I did some searching on the Internet about the name Zwicky's Triplet and not much came up.
Can anyone tell me why it's called Zwicky's Triplet and not just a Zwicky catalogue number.
And is PGC 59062, MCG+8-31-3, MCG+8-31-3A the Triplet or is NGC 6241 - UGC10586 the Triplet?
I really hope you can help me with this one.
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Lars
10", 8", 4" Newton
80mm Scopos
4" Achro
Edited by ZielkeNightsky (03/22/09 07:58 AM)
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Astrojensen
sage
Reged: 10/05/08
Posts: 219
Loc: Bornholm, Denmark
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Hej Lars
According to my old edition of Uranometria 2000.0, Zwicky's triplet is the northernmost galaxies, PGC 59062, MCG+8-31-3, MCG+8-31-3A or Arp 103.
As to just why it is called Zwicky's Triplet, well I don't know. I must admit, when I saw the name, I thought of II Zw 99 in Aquarius instead. In the world of deep-sky observing, one learns to live with mysteries like this one!
I find it pretty amazing that your MallinCam shows more detail than the DSS image.
Clear skies!
Thomas, Bornholm
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sgottlieb
sage
Reged: 07/22/07
Posts: 343
Loc: SF Bay area
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Here is Fritz Zwicky and Milton Humason's 1961 paper on "Spectra and Other Characteristics of Interconnected Galaxies and of Galaxies in Groups and in Clusters"
On page 804 of the journal article, they discuss "The Triple Interconnected Galaxy" with a schematic showing a long plume connecting the northeast member (MCG +08-31-003a) with the close pair PGC 59061/59062 = MCG +08-31-003 = CGCG 252-003). The luminous bridge is described in detail and it is mentioned that "a number of additional galaxies are located in the field of our triple galaxies...". But the diagram and description pins down the identification.
Here's what I logged back in 1998 with a 17.5-inch scope at 220x ---
The brightest member (PGC 59061) of Zwicky's Triplet was immediately picked up at 220x and appeared fairly faint, small, round, 30" diameter, even concentration to a small brighter core and stellar nucleus. The galaxy is located midway between two mag 12 stars 3.0' SSW and 2.8' NNE. with the third member of the triplet 2.4' NE.
On close inspection the main galaxy was noticed to be elongated approximately E-W and with concentration, a very small and faint spot (PGC 59062) was resolved just off the WSW side (26" between centers). At moments both galaxies were encased in a common halo but generally the challenging companion was detached.
The northeast component (PGC 59065 = MCG +08-31-003a) of Zwicky's Triplet is situated 2.4' NE of the CGCG 252-003 double system. This difficult galaxy was extremely faint, very small, round, 15" diameter. A mag 12.5 star is located less than 30" NE.
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Steve Gottlieb
18" f/4.3 Starmaster
Adventures In Deep Space
7500+ NGC/IC Visual Descriptions
NGC/IC Project
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ZielkeNightsky
sage
Reged: 10/01/06
Posts: 378
Loc: Denmark
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Thomas thanks, You must have viewed a broadcast or???
Steve,
Thanks for the information. This is great, the puzzle is solved. I wonder how you found this information/article. Do you have magic tricks in your astronomical gear?
Also thanks for the impressions with the 17.5" scope.
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Lars
10", 8", 4" Newton
80mm Scopos
4" Achro
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Astrojensen
sage
Reged: 10/05/08
Posts: 219
Loc: Bornholm, Denmark
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Quote:
Thomas thanks, You must have viewed a broadcast or??
Hej Lars
Næ, men jeg er på flere fora hver dag...
Anyway, I think you should have told the people here what you're working with.
Oh, and besides, a truly huge amount of info is buried in the web, if you know where to look.
Clear skies!
Thomas, Denmark
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Astrojensen
sage
Reged: 10/05/08
Posts: 219
Loc: Bornholm, Denmark
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Hej Lars
Here's a nifty link, in case you don't know about it:
http://adswww.harvard.edu/
Try to search "Zwicky, Fritz" or "Interacting galaxies" or anything and see what you get. Not all articles can be read online, though. I have used this service to read very old astronomy magazines such as "Astronomische Nachrichten" and "The Astronomical Register", which has given me a unique insight into the history of observational astronomy. Very few observers today bother to read such stuff, even if they know where to find it.
Clear skies!
Thomas, Bornholm, Denmark
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sgottlieb
sage
Reged: 07/22/07
Posts: 343
Loc: SF Bay area
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I've looked into the origin of the "Zwicky's Triplet" nickname before, but an easy way to search is through the bibliographic databases in NED (http://nedwww.ipac.caltech.edu/) and SIMBAD (http://simbad.u-strasbg.fr/simbad/).
In the case of NED, do a "Search by Name" on MCG +08-31-003 or one of the other designations. You'll find a list of aliases, coordinates, redshift, magnitude, diameter, classification type, images and more. If you scroll down past the thumbnail image, click the link to "12 references" and the 1961 paper is listed towards the bottom of the list of references. If you just want to go directly to a list of journal articles, you can search the astronomical literature in NED through a variety of links on the home page such as "References by Author Name".
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Steve Gottlieb
18" f/4.3 Starmaster
Adventures In Deep Space
7500+ NGC/IC Visual Descriptions
NGC/IC Project
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Dr Morbius
scholastic sledgehammer
Reged: 02/06/07
Posts: 1721
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"Zwicky's Triplet" I like. "Octomom's Octuplets" I had enough of!  
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Meade ETX-125
NightFire 6" f/8 Refractor with Moonlite focuser
Meade 14" LX200 S/C
D&G 10" f/15 Refractor with Parallax Mount
Little Giant 11x70mm Binos
I'm afraid of dying, but I've learned to live with it. ......Steve Perry
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MessierScott
sage
Reged: 06/18/07
Posts: 294
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Quote:
Here's what I logged back in 1998 with a 17.5-inch scope at 220x ---
The brightest member (PGC 59061) of Zwicky's Triplet was immediately picked up at 220x and appeared fairly faint, small, round, 30" diameter, even concentration to a small brighter core and stellar nucleus. The galaxy is located midway between two mag 12 stars 3.0' SSW and 2.8' NNE. with the third member of the triplet 2.4' NE.
On close inspection the main galaxy was noticed to be elongated approximately E-W and with concentration, a very small and faint spot (PGC 59062) was resolved just off the WSW side (26" between centers). At moments both galaxies were encased in a common halo but generally the challenging companion was detached.
The northeast component (PGC 59065 = MCG +08-31-003a) of Zwicky's Triplet is situated 2.4' NE of the CGCG 252-003 double system. This difficult galaxy was extremely faint, very small, round, 15" diameter. A mag 12.5 star is located less than 30" NE.
I like your logging notes Steve! Great minds must think alike? 
Here's mine from July 2006 at 209x with the 20-inch:
PGC59061 (MCG+8-31-3) is small and round with direct vision. Just a very slight. almost stellar, core brightness can be seen. And then with averted vision, the companion to the immediate SW, PGC59062, can be seen as a tiny round hazy smudge. About 2’ to the NNE of PGC59061, galaxy PGC59065 (MCG+8-31-3A) can be seen with direct vision. A/V shows no core, but just a slight hazy round ball. A 13th mag star lies immediately to it NE. At the far ESE edge of the FOV is galaxy NGC6241.
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Scott Kranz
20-inch f/4.3 Starmaster w/Zambuto mirror
7-inch Starmaster
H-alpha Coronado PST
Denkmeier II binoviewers w/24mm Panoptics
16x80 binos
Astronomical Society of Kansas City
Powell Observatory with 30-inch f/4.9 EQ newtonian
Astronomical League Messier, Meteor, Sunspotter, & Asteroid Observing Programs Coordinator
ASKC Dark Sky Site
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