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Darren Drake
professor emeritus
Reged: 10/09/02
Posts: 995
Loc: Illinois
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I saw this for the first time the other night through low transparency skies and could see only 3 members with certanty. How difficult is this cluster and how does it compare to Stephans Quintet? Also does anyone know the distances to these galaxies? I believe one is considerably more distant than the other 5. Thanks!
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Astronomy educator
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Cernan Space Center astronomer
Member of Northwest Suburban Astronomers
Edited by Darren Drake (07/31/08 11:35 AM)
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tatarjj
scholastic sledgehammer
Reged: 04/20/04
Posts: 890
Loc: Auburn, AL
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It's significantly harder to see all the members of Seyfert's Sextet than all the members of Stephan's quintet. I can easily make out all the members in Stephan's Quintet in my 18" telescope, but I could not separate Seyfert's Sextet into all six members. However, I was able to glimpse all six members of Seyfert's Sextet in my 25" scope in June.
Simbad gives a z of around 0.014 for the group. With an Ho of 70km/s/Mpc, that puts it at about 60Mpc or 200M light years.
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John T.
Auburn, AL
25" f/4.2 Dob
18" Obsession #701
4" Stellar Vue Achromat
8X56 Binos
Edited by tatarjj (07/31/08 02:28 PM)
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mv1000
member
Reged: 05/27/07
Posts: 90
Loc: WI
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I found it much more difficult than Stephans Quintet. Almost went past it. It's such a tight little group. I was unable to tell if there were seperate members.
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Starmaster 14.5 Hybrid
TV 60
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David Knisely
Postmaster
Reged: 04/19/04
Posts: 6498
Loc: Beatrice, Nebraska
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Quote:
I found it much more difficult than Stephans Quintet. Almost went past it. It's such a tight little group. I was unable to tell if there were seperate members.
Although I have detected the two brightest members of the group in a 10 inch, they are indeed quite faint and small. Here at the Nebraska Star Party, we went after the group in a 25 inch f/5 Obsession and had little trouble seeing the two central members (NGC 6027a and 6027b?), but the others were somewhat more difficult. The faint nearly edge-on spiral NGC 6027d on one end was visible as a fainter narrow streak, but the other members of the group were less-well defined. It was harder to pick out the "tidal tail" of the b component off the end of the group, and the other elliptical between the two brighter members tended to merge with them a bit. The little interloper in the group I didn't really see standing out all that much, but I may have seen it as a fuzzy star, since the seeing wasn't all that hot. Clear skies to you.
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David W. Knisely
Hyde Memorial Observatory
http://www.hydeobservatory.info
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sgottlieb
sage
Reged: 07/22/07
Posts: 220
Loc: SF Bay area
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In good conditions, the three brightest members are routinely resolved in my 18" Starmaster at 250x-325x but I've never even suspected the fainter members.
In fact, even in Alvin's 30" Starmaster the other members were difficult and the virtually stellar member appeared as you might guess... stellar! Perhaps Alvin can provide more details.
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Steve Gottlieb
18" f/4.3 Starmaster
Adventures In Deep Space - New article on MASH planetaries
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planetman83
member
Reged: 09/17/07
Posts: 35
Loc: Greece-Crete
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I have seen both seyfert's sextet and stephan's quintet with my 8" dob and I think that the seyfert's sextet is easiest to be glimpsed but its members are more difficut to be splitted maybe because they are more. I think the stephan's quintet is generally a more difficult object.
Edited by planetman83 (08/13/08 06:49 AM)
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Alvin Huey
Pooh-Bah
Reged: 10/18/05
Posts: 1430
Loc: NorCal
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I didn't see this thread 'till now. I have my notes at home. I'll try and remember to post bak when i get to it late tonight. I do remember that very high powers and good seeing is key to resolving the 6 members. I was able to do it on a couple occasions.
I'll post my notes later.
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Clear Skies,
Alvin #26
22" f/4.1 reflector, Takahashi TOA-130S on AP1200GTO, 30" f/4.3 StarMaster and Antares 6" f/6.5 on Orion SVP
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Bill Weir
professor emeritus
Reged: 06/01/04
Posts: 708
Loc: Metchosin (Victoria), Canada
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On Saturday night at the approx 1900 m site of the Mt Kobau Star Party. I was able to determine 3 members. I was using my 12.5" dob at 365X. The two with the widest separation (I'm assuming NGC 6027 and 6027 E) held steady with averted vision. The third (6027 A?) was quite close to another, and flickered in and out, but was clearly a separate object.
I had only looked at them because I had noticed them on the same page of my Uranometria after observing Abell Galaxy Cluster 2151. Now, observing Abell 2151 with my 12.5" was exciting too. At one point, at 152X I was seeing a total of 10 galaxies winking on and off at one time in the FOV.
Bill
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6'' Orion SkyQuest
12.5'' f/5 Custom Truss Dob
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Observing sessions grand total for 2007, 171.
So far in 2008, 87
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sgottlieb
sage
Reged: 07/22/07
Posts: 220
Loc: SF Bay area
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Quote:
On Saturday night at the approx 1900 m site of the Mt Kobau Star Party. I was able to determine 3 members. I was using my 12.5" dob at 365X. The two with the widest separation (I'm assuming NGC 6027 and 6027 E) held steady with averted vision. The third (6027 A?) was quite close to another, and flickered in and out, but was clearly a separate object.
Bill, your description closely matches the appearance in my old 13.1" Coulter dob. The smallest object, by the way, (your third) is HCG 79C and is located just off the west edge of HCG 79A. Also adding to the crowded scene are a couple of mag 14.5 stars just east of the clump of the galaxies and a slightly brighter mag 14 star close west.
By the way, it was Edouard Stephan, of Stephan's Quintet fame, who really discovered this group visually. He only logged a single object, but based on his description "eF, vF* inv, 2 vF st nr" I thinks it's likely that his "vF* involved" was actually the second cluster member and it's possible that one or two of his "2 vF st nr" was the third member! After all, in 1882 when he made the discovery, Stephan was using a 31.5-inch silver-on-glass reflector.
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Steve Gottlieb
18" f/4.3 Starmaster
Adventures In Deep Space - New article on MASH planetaries
7500+ NGC/IC Visual Descriptions
NGC/IC Project
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Alvin Huey
Pooh-Bah
Reged: 10/18/05
Posts: 1430
Loc: NorCal
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Here are my observations.
This is the famous Seyferts Sextet a nice challenging group of five galaxies stuffed into a circle of about 1.5. In viewing this object, I swapped between the 5mm (528x) and 3mm (881x) Radians trying to bust apart the closely-knit galaxies, which I succeeded.
NGC 6027E was originally thought by Seyfert as the sixth galaxy but it turns out to be a faint extension from NGC 6027B.
Component A (NGC 6027A) Easily the brightest member of the group. It is a 2:1 elongated patch with a brighter center. Estimated size is about 30 on the major axis. Less than 30 north lies NGC 6027B. NGC 6027C lies 30 SE. NGC 6027 lies 30 NE. PA = 80˚
Component B (NGC 6027B) This galaxy shows a very bright highly concentrated 3:1 spindle. The core has a very high surface brightness. Second brightest member of the group. The size is about 20 by 7. PA = 90˚
Component C (NGC 6027) Pretty concentrated and small 2:1 oval. Fairly high surface brightness, about the same as NGC 6027A. Its estimated size is about 20 by 10. PA = 20˚
Component D (NGC 6027C) This edge-on is a very thin faint line with no condensation. This member was pretty difficult and needed 528x to see it. Averted vision doesnt give it any more size, which is about 30 long. PA = 0˚
Component E (NGC 6027D) This galaxy shows an extremely small faint round spot almost touching the southeast end of NGC 6027. The surface brightness is the same as NGC 6027, just the size at about 10 that makes this one a toughie. Needed 881x to separate the two galaxies.
Component x (NGC 6027E) A very low surface brightness 2:1 oval with even surface brightness. No central concentration was seen. I estimate the visible size to be about 30 on the major axis. PA = 45˚
Sketch with the 22 f/4.1 reflector at 881x. Field = 4.1' Transparency 8/10, Seeing 8/10 NELM = 6.8
Edited by Alvin Huey (08/13/08 01:53 AM)
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