Go Back   IceInSpace > General Astronomy > Observational and Visual Astronomy
Register FAQ Calendar Today's Posts Search

Reply
 
Thread Tools Rate Thread
  #1  
Old 13-02-2011, 09:34 PM
pgc hunter's Avatar
pgc hunter
Registered User

pgc hunter is online now
 
Join Date: Feb 2009
Location: Renmark, SA
Posts: 2,993
Sirius B

Just a short report of my observation of Sirius B on the 17th January 2011.

I was using the 12" dob. Seing was average, nothing special but not bad either. I've had luck on previous occasions using my 3.5mm and 5mm eyepieces, but never attempted lower magnifications. Started off with the 3.5mm (381x), and the pup was quite easy to see. Through the 5mm EP (267x) it proved no more difficult. Then I tried the 8mm (167x), with which the pup was still plainly visible, but Sirius' glare was starting to hinder observation, especially with the boiling effect of the seeing. Then I barlowed the 22mm EP for 121x, and the pup could still be just seen, but only occasionally in moments of steady seeing. Hard concentration was required, certainly no casual looks here! Decided to go one lower, so in goes the 13mm for 102x, and to my surprise, it could still be spotted, although very irregularly, and only in split second instances as the seeing did its dirty work. Anything lower obviously killed it completely, I'm surprised it can be picked up at this lower magnifications.
Reply With Quote
  #2  
Old 13-02-2011, 10:26 PM
Suzy's Avatar
Suzy
Searching for Travolta...

Suzy is offline
 
Join Date: Jan 2010
Location: Brisbane, Australia.
Posts: 3,700
I interesting! Thanks Sab. I always thought it was beyond me at the moment as I'm fairly new to observing and have heard this is tricky to get. This gives me hope with useful information to help me.
I've heard this Sirius B (the pup) gets easier to see when it comes out at certain times (?), is now the time that is good to see it? And how often are the times of viewing it? Sorry about so many questions, learning here...
Reply With Quote
  #3  
Old 13-02-2011, 10:31 PM
barx1963's Avatar
barx1963 (Malcolm)
Bright the hawk's flight

barx1963 is offline
 
Join Date: Nov 2008
Location: Mt Duneed Vic
Posts: 3,982
The Pup at 102!!!
Sab you are the man
Reply With Quote
  #4  
Old 13-02-2011, 11:51 PM
Brian W's Avatar
Brian W (Brian)
The Wanderer

Brian W is offline
 
Join Date: Jan 2008
Location: Dumaguete Philippines
Posts: 757
Suzy a couple of weeks back I caught the pup at 94x in my 8" Lightbridge. If I can do it anyone can. Now mind, when I slipped in my 2.5mm it was much more pronounced but certainly more fuzzy. (not a great night).
Brian
Reply With Quote
  #5  
Old 14-02-2011, 12:32 AM
AstroJunk's Avatar
AstroJunk (Jonathan)
Shadow Chaser

AstroJunk is offline
 
Join Date: Jan 2006
Location: Moonee Beach
Posts: 1,945
Sirius B is currently at 90 degrees PA - thats due East of Sirius and at a separation of over 10 arc seconds which is now quite wide. Its easier to see when you know where to look!

If Sirius is on the meridian, it will be on the right in an SCT, the left on a newt if i'm not mistaken. If you are not using a driven telescope, let the star drift for a while - the angle it drifts marks the e-w line for your scope.

http://www.youtube.com/watch?v=K9m5MW5HMl4 &

http://www.youtube.com/watch?v=lKwSdrTWeJM

I have been watching the two move apart for that past few years but have to admit not having looked visually yet this year.

Well done all for spotting it its one of the toughest challenges out there
Reply With Quote
  #6  
Old 14-02-2011, 12:49 AM
ballaratdragons's Avatar
ballaratdragons (Ken)
The 'DRAGON MAN'

ballaratdragons is offline
 
Join Date: Jan 2005
Location: In the Dark at Snake Valley, Victoria
Posts: 14,412
I might be way off, but would it be slightly easier to see the pup during daylight hours?

The few times I have observed stars in daylight they are more pinpoint and definitely not as glaring. Maybe worth a try.
Reply With Quote
  #7  
Old 14-02-2011, 11:43 AM
AstroJunk's Avatar
AstroJunk (Jonathan)
Shadow Chaser

AstroJunk is offline
 
Join Date: Jan 2006
Location: Moonee Beach
Posts: 1,945
Thats an interesting thought, but I believe that the background sky magnitude is around 4 (Willing to stand corrected on the actual number), but even so, the Pup is just too dim.

It could be worth observing it during the twilight transition though, there could be a perfect moment...
Reply With Quote
  #8  
Old 14-02-2011, 06:59 PM
mozzie's Avatar
mozzie (Peter)
Registered User

mozzie is offline
 
Join Date: Mar 2007
Location: moonee beach
Posts: 2,179
wow some interesting information thanks all!!! i tried a few years back with no luck now seems like the go........
Reply With Quote
  #9  
Old 14-02-2011, 07:24 PM
pgc hunter's Avatar
pgc hunter
Registered User

pgc hunter is online now
 
Join Date: Feb 2009
Location: Renmark, SA
Posts: 2,993
Quote:
Originally Posted by Suzy View Post
I interesting! Thanks Sab. I always thought it was beyond me at the moment as I'm fairly new to observing and have heard this is tricky to get. This gives me hope with useful information to help me.
I've heard this Sirius B (the pup) gets easier to see when it comes out at certain times (?), is now the time that is good to see it? And how often are the times of viewing it? Sorry about so many questions, learning here...
Hey Suzy, you are a shoe-in with the 10" scope. You'll need atleast average seeing, wait for Sirius to be as high as possible, and pump up the power. The pup is directly east of Sirius, the seperation is about 9" IIRC. Note the direction Sirius drifts across the field, and look for the pup directly "behind" it (trailing it). It'll show up as a tiny pip of light, but make sure you don't get fooled by reflections of Sirius itself caused by the glass elements in your eyepieces, as these can appear suprisingly like the little dog itself!


Quote:
Originally Posted by ballaratdragons View Post
I might be way off, but would it be slightly easier to see the pup during daylight hours?

The few times I have observed stars in daylight they are more pinpoint and definitely not as glaring. Maybe worth a try.
Don't think the pup is visible in daylight. Just too dim it would seem. Astrojunk's idea of a twilight hunt sounds interesting and might actually be superior to full darkness, much like when observing fine detail on Jupiter. Haven't heard any reports of anyone attempting a twilight observation, so I'm keen to try it if the opportunity presents itself.

Quote:
Originally Posted by barx1963 View Post
The Pup at 102!!!
Sab you are the man
Cheers mate!
Reply With Quote
  #10  
Old 14-02-2011, 08:24 PM
ballaratdragons's Avatar
ballaratdragons (Ken)
The 'DRAGON MAN'

ballaratdragons is offline
 
Join Date: Jan 2005
Location: In the Dark at Snake Valley, Victoria
Posts: 14,412
Quote:
Originally Posted by pgc hunter View Post
Don't think the pup is visible in daylight. Just too dim it would seem. Astrojunk's idea of a twilight hunt sounds interesting and might actually be superior to full darkness, much like when observing fine detail on Jupiter. Haven't heard any reports of anyone attempting a twilight observation, so I'm keen to try it if the opportunity presents itself.
Yes, exactly. I don't mean go looking for it in broad daylight on a sunny day

All my daytime observations have been early twilight. At Sunset and just after
Still light but not bright.

P.S. About right now would be perfect!
Reply With Quote
  #11  
Old 14-02-2011, 10:11 PM
AstroJunk's Avatar
AstroJunk (Jonathan)
Shadow Chaser

AstroJunk is offline
 
Join Date: Jan 2006
Location: Moonee Beach
Posts: 1,945
Quote:
Originally Posted by ballaratdragons View Post
P.S. About right now would be perfect!
Not in Cloudy Qld
Reply With Quote
  #12  
Old 14-02-2011, 10:38 PM
CometGuy's Avatar
CometGuy
Registered User

CometGuy is offline
 
Join Date: Feb 2005
Location: Brisbane
Posts: 942
Since I got my new 12" Scope I believe I have been able to see Sirius B twice. On both occasions it was not particularly easy, but to be honest I was expecting it to be more challenging than what it was. I think the increasing separation between the 2 stars in recent years is helping a lot with visibility.

Ken if you try just after sunset you should be able to see it.

Anyway here is a sketch of roughly what I saw on Feb 4, 2011, at 375x.

Terry
Attached Thumbnails
Click for full-size image (sirius_375x.jpg)
15.3 KB65 views
Reply With Quote
  #13  
Old 14-02-2011, 11:22 PM
AstroJunk's Avatar
AstroJunk (Jonathan)
Shadow Chaser

AstroJunk is offline
 
Join Date: Jan 2006
Location: Moonee Beach
Posts: 1,945
Sirius is notorious for creating false images in eyepieces. To confirm a result you really must know what 10 arc seconds is in your eyepiece.

have a look at the this page: http://www.astropix.com/HTML/B_WINTER/TRAPEZ.HTM the diagram of the trapezium shows the distances between stars - so we are talking the distance between a and b.

Then make absolutely sure it is in the correct position (90 degrees east of north)

If it isn't very hard indeed, it isn't the pup!
Attached Thumbnails
Click for full-size image (trapezium.jpg)
102.8 KB51 views
Reply With Quote
  #14  
Old 16-02-2011, 08:14 PM
CometGuy's Avatar
CometGuy
Registered User

CometGuy is offline
 
Join Date: Feb 2005
Location: Brisbane
Posts: 942
Hi Jonathan,

I'm quite sure of this observation. I checked PA (using the drift method) and comparision with the Rigel suggested the angular separation was correct as well.

With regard to false images, the one thing that makes discount this was the fact that companion moved with Sirius across the field. It kept its position relative to Sirius, and a reflection would not tend to do this.

Good seeing I think plays a big part, as the slightest amount of fuzziness will obscure the star within the glare of Sirius. Also my scope is very new and the eyepieces were cleaned prior to observation, so scattered light was minimised.

I should also say I have tried to split Sirius for many years and had never succeeded.

Terry
Reply With Quote
  #15  
Old 16-02-2011, 10:00 PM
AstroJunk's Avatar
AstroJunk (Jonathan)
Shadow Chaser

AstroJunk is offline
 
Join Date: Jan 2006
Location: Moonee Beach
Posts: 1,945
Good work Terry, and you remind me of another important thing to do when looking at Sirius - go check another bright star that such as rigel or canopus and look for reflections too.
Reply With Quote
  #16  
Old 16-02-2011, 10:27 PM
ballaratdragons's Avatar
ballaratdragons (Ken)
The 'DRAGON MAN'

ballaratdragons is offline
 
Join Date: Jan 2005
Location: In the Dark at Snake Valley, Victoria
Posts: 14,412
I spent a couple of hours experimenting with my Samsung AstroVideo camera today to place a small mask in the live feed so I can mask Sirius out and video the Pup, and typical! Thunderstorms

Here is a Screen Grab of how it works on my Lounge-room ceiling.
I can make the mask any size I want, right down to 1 pixel x 1 pixel, and move it to any location in the FOV.
Only thing I can't do is make it round.
Attached Thumbnails
Click for full-size image (Star-Mask-test.jpg)
81.4 KB15 views
Reply With Quote
  #17  
Old 16-02-2011, 10:41 PM
pgc hunter's Avatar
pgc hunter
Registered User

pgc hunter is online now
 
Join Date: Feb 2009
Location: Renmark, SA
Posts: 2,993
Quote:
Originally Posted by AstroJunk View Post
Sirius is notorious for creating false images in eyepieces. To confirm a result you really must know what 10 arc seconds is in your eyepiece.

have a look at the this page: http://www.astropix.com/HTML/B_WINTER/TRAPEZ.HTM the diagram of the trapezium shows the distances between stars - so we are talking the distance between a and b.

Then make absolutely sure it is in the correct position (90 degrees east of north)

If it isn't very hard indeed, it isn't the pup!
Looking at that pic makes me realise how hard the G and H components of the trapezium are. The E and F are ludicrously easy, so after Sirius B the G/H is my next challenge.
Reply With Quote
  #18  
Old 16-02-2011, 11:02 PM
AstroJunk's Avatar
AstroJunk (Jonathan)
Shadow Chaser

AstroJunk is offline
 
Join Date: Jan 2006
Location: Moonee Beach
Posts: 1,945
Quote:
Originally Posted by pgc hunter View Post
The E and F are ludicrously easy...
You are beginning to sound like a true SDM owner now The joy of owning a top quality mirror
Reply With Quote
  #19  
Old 17-02-2011, 05:29 PM
pgc hunter's Avatar
pgc hunter
Registered User

pgc hunter is online now
 
Join Date: Feb 2009
Location: Renmark, SA
Posts: 2,993
Quote:
Originally Posted by AstroJunk View Post
You are beginning to sound like a true SDM owner now The joy of owning a top quality mirror
lol I never found the E/F components to be any big deal and can split them at 80x, and even here it's more my own astigmatism that's the limiting factor.
Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 10:10 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement