Return to the Cloudy Nights Telescope Reviews home page


Observing >> Double Star Observing

Pages: 1
brucepiano
sage


Reged: 12/02/07

Loc: New England
M11 new
      #6045115 - 08/25/13 12:36 PM

What is the designation and magnitude for the double star in the center of Messier 11?

Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: M11 new [Re: brucepiano]
      #6045128 - 08/25/13 12:48 PM

WDS18511-0617
8.0-12.4v, 5.8" @191PA

Per Sky Safari

Pete


Post Extras: Print Post   Remind Me!   Notify Moderator  
PJ AnwayModerator
Double-Star Observer
*****

Reged: 06/04/03

Loc: North Coast
Re: M11 new [Re: brucepiano]
      #6045614 - 08/25/13 05:53 PM

J(Jonckheere) 107AB

8.47 - 11.34 mag., 6.39" sep, 192 p.a.


Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: M11 new [Re: PJ Anway]
      #6045790 - 08/25/13 07:27 PM

PJ,

Your information is spot on. I update my Sky Safsri when they ask for it but itd be nice if it truly did that. I'm guessing my info is outdated and possibly wrong on magnitude.

Thanks.

Pete


Post Extras: Print Post   Remind Me!   Notify Moderator  
brucepiano
sage


Reged: 12/02/07

Loc: New England
Re: M11 new [Re: azure1961p]
      #6046095 - 08/25/13 10:09 PM

I don't have Sky Safari, but I could download it for my IPOD touch. Was the center star of the cluster visible, and you just clicked on it to get the listing?

Post Extras: Print Post   Remind Me!   Notify Moderator  
WRAK
Pooh-Bah


Reged: 02/18/12

Loc: Vienna, Austria, Europe
Re: M11 new [Re: brucepiano]
      #6046515 - 08/26/13 07:57 AM

Did you resolve J107 with your 10" scope?
Wilfried


Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: M11 new [Re: WRAK]
      #6046524 - 08/26/13 08:07 AM Attachment (16 downloads)

Yes. Had to zoom in a but though.

Here's how it looks:


Pete

Edited by azure1961p (08/26/13 08:08 AM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
WRAK
Pooh-Bah


Reged: 02/18/12

Loc: Vienna, Austria, Europe
Re: M11 new [Re: azure1961p]
      #6046560 - 08/26/13 08:53 AM

See now that it is acually a multiple star with maybe 4 or more components.
Wilfried


Post Extras: Print Post   Remind Me!   Notify Moderator  
blb
Post Laureate


Reged: 11/25/05

Loc: Piedmont NC
Re: M11 new [Re: WRAK]
      #6046592 - 08/26/13 09:14 AM

Quote:

See now that it is acually a multiple star with maybe 4 or more components.



When does a multiple star become a small cluster and no longer a multiple star? Are not all open clusters gravitionaly bound together?


Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: M11 new [Re: blb]
      #6046656 - 08/26/13 10:01 AM

I thought the qualifier for a double or multiple system was that all orbited about each other in defined cyclical paths. An open cluster while gravitationally bound to its members and changes shape over the eons, has no such cyclical orbital behavior. Not to say some members of an OC don't orbit each other as doubles and multiple systems abound in these things. But the cluster as a whole isn't orbiting around its seperate members.

Pete


Post Extras: Print Post   Remind Me!   Notify Moderator  
GlennLeDrew
Postmaster
*****

Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: M11 new [Re: azure1961p]
      #6046785 - 08/26/13 11:10 AM

Double and multiple stars do exist in clusters. In older and more populated clusters, hard binaries are more likely to exist than soft binaries, as their small orbit and hence strong binding makes them more resistant to the effects of tides and encounters with other cluster members. And so there are many more spectroscopic binaries in clusters than there are optically resolved ones.

Post Extras: Print Post   Remind Me!   Notify Moderator  
brucepiano
sage


Reged: 12/02/07

Loc: New England
Re: M11 [Re: WRAK]
      #6046841 - 08/26/13 11:43 AM

If you are referring to the central star in the cluster- yes, but barely. A few nights ago was the best view of M11 I have had. It was also on the meridian. I could barely split it with the Hyperion 13mm, and Siebert Optics 5.9 Star Splitter. The latter was a little better. But I could see a double.

I also use the Orion Lights out cape, which improves the view about 10-15% and blocks out light. The cape is especially good for doubles, and open clusters.

In a bright open cluster, such as the Double Cluster, or M11, the effect of blocking out light is quite noticeable.


Post Extras: Print Post   Remind Me!   Notify Moderator  
WRAK
Pooh-Bah


Reged: 02/18/12

Loc: Vienna, Austria, Europe
Re: M11 new [Re: brucepiano]
      #6047396 - 08/26/13 05:38 PM

I found the following entries in the WDS catalog:
Name - m1 - - m2 - -sep -pos
J107AB 08,62 11,34 06,3 192
J107AC 08,62 11,89 09,9 147
J107CD 11,89 12,20 03,6 197
J107AE 08,62 12,50 15,8 093
J107EF 12,50 12,70 03,4 327
Sounds nice. M11 is one of my favorite open clusters and J107 seems just another reason to visit it again.
But what did you now see exactly? All members of this multiple should be easy to resolve with 10" aperture.
Wilfried


Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: M11 new [Re: WRAK]
      #6047669 - 08/26/13 08:42 PM Attachment (13 downloads)

Here's a clise in shot- doubles appear here and there but no designations. Field of view in the screen shot for scale.


Pete

Edited by azure1961p (08/26/13 08:43 PM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
GlennLeDrew
Postmaster
*****

Reged: 06/18/08

Loc: Ottawa, Ontario, Canada
Re: M11 new [Re: azure1961p]
      #6048098 - 08/27/13 01:40 AM

I would not be surprised if one or more of the resolved doubles in this cluster (and others) are just line-of-sight pairings of cluster singletons.

Post Extras: Print Post   Remind Me!   Notify Moderator  
brucepiano
sage


Reged: 12/02/07

Loc: New England
Re: M11 new [Re: azure1961p]
      #6048273 - 08/27/13 07:17 AM

I am not getting all these stars in my version- educational. The double NE of the center with a bluish star in your pic does not show up in my version.
Where are the boundaries of the cluster? Is S Scuti in the cluster? I may want to upgrade.


Post Extras: Print Post   Remind Me!   Notify Moderator  
brucepiano
sage


Reged: 12/02/07

Loc: New England
Re: M11 new [Re: WRAK]
      #6048277 - 08/27/13 07:26 AM

I could barely resolve one component- the star just SE of HD 174512.

Post Extras: Print Post   Remind Me!   Notify Moderator  
azure1961p
Postmaster
*****

Reged: 01/17/09

Loc: USA
Re: M11 new [Re: brucepiano]
      #6048292 - 08/27/13 07:42 AM

The boundaries are beyond the field of view in the screenshot as it was zoomed in very tight.

Pete


Post Extras: Print Post   Remind Me!   Notify Moderator  
blb
Post Laureate


Reged: 11/25/05

Loc: Piedmont NC
Re: M11 new [Re: azure1961p]
      #6048574 - 08/27/13 10:44 AM

Quote:

Where are the boundaries of the cluster? Is S Scuti in the cluster? I may want to upgrade.



I noticed in the upper right hand corner of the above screenshot that the field-of-view was only 4.2'x6.6' in size. Most sources list the size of M11 as being about 14' in diameter, so this screenshot is only a small portion of the center of the cluster. To see the edge of the cluster you would need to zoom out for a screen size that is larger than the cluster.


Post Extras: Print Post   Remind Me!   Notify Moderator  
brucepiano
sage


Reged: 12/02/07

Loc: New England
Re: M11 new [Re: blb]
      #6048620 - 08/27/13 11:14 AM

I also found that when I downloaded 3plus, I could see many more stars in M11. It looked similar to the view in my scope.
However, it was more difficult to identify the central star found in the basic version. The double I thought I was looking may not be a double and is a Tycho star 5126-4051-1. I flipped my screen vertically( disabling rotation) and I found that I couldn't find the central star in the cluster.

But I was able to locate the central star using the HD designation.

The 3plus app is much more comprehensive than the basic for doubles.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1


Extra information
2 registered and 2 anonymous users are browsing this forum.

Moderator:  PJ Anway, Rich (RLTYS), rflinn68 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 536

Jump to

CN Forums Home




Cloudy Nights Sponsor: Astronomics