It's that season again - the hunt for "the Pup Star" - Sirius B

[John]

21 minutes ago, Ags said:

Good info, thanks! What's the diameter of that circle?

The whole field is around 12 arc minutes in diameter (1/5th of a degree approx) and the red circles are around 15-20 arc seconds in diameter I would estimate. The current separation between Sirius A (the centre of that mass of light) and Sirius B is around 11 arc seconds. These are rough figures of course !

Edited January 9 by John

[Mr Spock]

A chart from CdC with the circle set at 15'

 

[MalcolmM]

I'm pretty sure I got it tonight, under strange circumstances!

I was using the 100DC with the Maxbrights, x2.6 GPC and 28mm Erfles. I started with the moon and the views were rubbish. It looked like I was looking through a band of driving horizontal rain! The image wasn't just wobbling, it was being ripped apart! This persisted for 5 minutes before I gave up, intending to call it a night.

A quick look at Rigel and I could just about split it and then remembering this thread thought, "why not!".

So I turned to Sirius and a very light layer of cloud or smog or mucky atmosphere rendered Sirius as a slightly wooly disk rather than the usual flashing disco ball. I thought I saw something at the 6.30 position (see attached pic). Don't know why, but I looked through each eyepiece with my left eye. Nothing in the left eyepiece, but a definite hit through the right eyepiece. No need for averted vision, it was there permanently. I swapped in 18mm and then 12.5mm Tak Abbe eyepieces and got the same result. Nothing in the left eyepiece, obvious in the right! 

I wonder is it possible that the dulling effect of the seeing, due to light cloud/smog/muck, dimmed the usual glare of Sirius making the Pup much easier to spot?

Just as a sanity check, I checked out the moon again and the seeing was pretty good. What a difference 10 minutes can make!

Anyway, barring a weird internal reflection in the Maxbrights, or my brain playing tricks on me, or someone reading this telling me it's in completely the wrong position, having only logged a possible sighting before, I'm going to log this one as a hit!

Malcolm 

[John]

7 minutes ago, MalcolmM said:

I'm pretty sure I got it tonight, under strange circumstances!

I was using the 100DC with the Maxbrights, x2.6 GPC and 28mm Erfles. I started with the moon and the views were rubbish. It looked like I was looking through a band of driving horizontal rain! The image wasn't just wobbling, it was being ripped apart! This persisted for 5 minutes before I gave up, intending to call it a night.

A quick look at Rigel and I could just about split it and then remembering this thread thought, "why not!".

So I turned to Sirius and a very light layer of cloud or smog or mucky atmosphere rendered Sirius as a slightly wooly disk rather than the usual flashing disco ball. I thought I saw something at the 6.30 position (see attached pic). Don't know why, but I looked through each eyepiece with my left eye. Nothing in the left eyepiece, but a definite hit through the right eyepiece. No need for averted vision, it was there permanently. I swapped in 18mm and then 12.5mm Tak Abbe eyepieces and got the same result. Nothing in the left eyepiece, obvious in the right! 

I wonder is it possible that the dulling effect of the seeing, due to light cloud/smog/muck, dimmed the usual glare of Sirius making the Pup much easier to spot?

Just as a sanity check, I checked out the moon again and the seeing was pretty good. What a difference 10 minutes can make!

Anyway, barring a weird internal reflection in the Maxbrights, or my brain playing tricks on me, or someone reading this telling me it's in completely the wrong position, having only logged a possible sighting before, I'm going to log this one as a hit!

Malcolm 

 

Nice report but the position angle does not seem quite right 🤔

@Mr Spock's chart posted above has it at the correct position I reckon. The field shown is about what I get at 250x. 

Unless binoviewers change the orientation of the view - I don't use them myself.

 

[MalcolmM]

10 hours ago, John said:

Nice report but the position angle does not seem quite right 🤔

@Mr Spock's chart posted above has it at the correct position I reckon. The field shown is about what I get at 250x. 

Unless binoviewers change the orientation of the view - I don't use them myself.

 

Mmmmm, the more I thought about it last night the more I thought it didn't look right. When I went back to check my notes of my possible sighting last time, it was in a different position. I think the concensus then was that that position was correct. 

So back to the drawing board ☹️ and I think I'll stick with mono viewing next time, though the binoviewers do not alter the orientation.

I'm beginning to wonder was it even Sirius I was looking at, though it's hard to miss! Maybe I'll post a pic in @Stu's headgear thread with my Dunce's hat on

Malcolm 

[John]

I'm not a binoviewer user but I wonder if they add some light scatter to the view, even the really good ones ?

Light scatter is a killer when trying to see the Pup star, whether it's from the atmosphere, central heating plumes, optics or observers eye. 

 

[Zermelo]

39 minutes ago, John said:

Light scatter is a killer when trying to see the Pup sta

I may have missed it, John, but have you yet tried for the Pup with the Svbony planetary zoom? Light scatter was the main focus when I was comparing mine with other EPs, and I'm still undecided about how much was inherent and how much down to external factors.

[John]

4 hours ago, Zermelo said:

I may have missed it, John, but have you yet tried for the Pup with the Svbony planetary zoom? Light scatter was the main focus when I was comparing mine with other EPs, and I'm still undecided about how much was inherent and how much down to external factors.

Not yet, but I will once storm "whatever it is" has passed and we get some clear skies again 🙂

[JeremyS]

2 hours ago, John said:

Not yet, but I will once storm "whatever it is" has passed and we get some clear skies again 🙂

Tho this storm has some astronomical significance being named after Dame Jocelyn Bell Burrell, discoverer of pulsars 👍🏻

[F15Rules]

8 hours ago, John said:

I'm not a binoviewer user but I wonder if they add some light scatter to the view, even the really good ones ?

Light scatter is a killer when trying to see the Pup star, whether it's from the atmosphere, central heating plumes, optics or observers eye. 

 

I've managed the Pup several times John, as you know, (Vixen ED103s apo 4" and Takahashi FS128 5"), but I've never yet managed it with Binoviewers.. and I doubt I ever will.

I think Binoviewers reduce light transmission by maybe around half a magnitude or so.. also, however good and well aligned BVs seem to be, I feel that you cannot improve on a single high quality image with a double image..the double image surely is unlikely to ever combine to give the 100% equal of a perfect single eyepiece image?

That's why I still prefer cyclops viewing for double star observing..you get the brightest, tightest image your optical train can deliver..the remaining variable apart from sky conditions is then the acuity of your eye..😉

Dave

[JTEC]

Ouch … what was it I saw on the night of the 18th then? 🙂

I clocked it conclusively using the following kit:  TEC 140 apo, Zeiss Baader 2” prism diagonal, Zeiss MkV bino, 1.25 GPC and pair of Tak ortho eyepieces (9mm from memory).  All of that is, of course, high quality kit, arguably - unless you’re a Tak owner 🙂 - second to none, and it was all clean and in excellent nick.  The mount was an AZ100 on a Berlebach Planet tripod.
 

The seeing was very good. Earlier, views of the Moon had been astonishing.  
 

There are plenty of optical components in the above to produce troublesome scatter - but they didn’t. Quality coatings help perhaps, clean optics, ‘simple’ eyepieces and the use of a prism instead of a mirror diagonal?  Late last year, I sent the objective back to TEC for a once-over, a clean and a re-oil. They also blackened the edges of the objective which, apparently, they now routinely do - I bought the scope 18 years ago and, back then, they didn’t.  Yuri’s advice, incidentally, was to use ‘small and simple’ eyepieces for critical work.  I have a 13mm Ethos, a 10 mm Delos and a couple of XWs and I think they’re wonderful, about in that order, but, with my scope, the orthos edge them for critical viewing.  

I can only report my own experience, of course!  So much astronomy boils down to optimising each one of a number of ingredients, maybe this is a case in point - there were no real weak links in the visual chain … at least, until the light got to me! 🤣