After last weeks 'oh so close' encounter with Sirius B, I was enthusiastic to get out and have another go at finding

the elusive white dwarf.  Having clearly seen 'B' on my DSLR images I felt confident I could find it visually.  Last nights Astro-Cafe at Davis Bay had a very turbulent atmosphere.  Several of us had compared

views of Rigel and its double in 8" and 10" Newtonians.  It was barely detectable in the 8".  But tonight the

atmosphere seemed a little more steady and being up the hill - 250ft altitude - and away from the ocean I

figured I had a good chance.




20:30 PST

I wanted to try Celestron's Software Assisted Polar Alignment and so I did a quick check by putting Polaris in the

centre of the Polar Scope.  I found I could not put the telescope on Polaris  no matter what position I moved the

mount to.  This told me the telescope was not parallel to  the RA Axis - and would be a big problem for accurate tracking \- but not for visual.  I brought out some spanners and adjusted the rear of the OTA on the rail.  I couldn't fully

correct the problem out on the driveway, but was able to bring Polaris within the FOV of a 42mm E.P.

A half hour had slipped past and I was anxious to slew to Sirius. 



(I would need everyone of the Scopes light baffles

to baffle the nearby blazing street lights)




21:10 PST

My first impression was that Sirius looked a little more defined than previously.  I was using an Antares 4.3mm W70 EP

with 2" Antares 1.6x Barlow for 298x.  I was surprised to see the same 3 reflection ghosts that had plagued me on

an earlier observation.  I moved my eye around to see what effect that had on the reflections. 

Suddenly I had a revelation.  Two of the faint light echoes were ever present.  What if they were

really faint stars?  I had to use averted vision to convince myself these really were faint stars. 

Then a bright white point of light appeared below them dancing in the atmosphere - moving more than

I have ever seen a star move.  It was clear and precise and persisted for around 5 seconds before

disappearing for about the same time, then reappearing again.  I was stunned!  This is Sirius B!  No wonder I hadn't seen it before - its appearance (and disappearance) was not what I expected.  Rather than a faintly visible hard to focus star, I was seeing a clear (dare I say bright) white point of light; much more defined than the other field stars.  I watched Sirius B appear and disappear over several minutes.  I was elated, finally Sirius B.  In only my 3rd attempt of trying.  Quite an achievement I thought.  I should phone someone!  I decided I should attach my camera and get some photographic confirmation.  I spent some time taking images at various exposures.  Then I used a 25mm EP with a 1.6x Barlow for 51x.  I wanted to confirm my orientation by noting the field stars around Sirius. 



(Transcribed from my notes at the scope)




22:05 PST

Around 45 minutes had passed since my first sighting and I wanted to confirm Sirius B's position now that some time had passed.  However my 4.3mm EP had fogged up quite badly.  I put the 4.3 EP in my pocket to warm up and used my

13mm 2" EP instead. I also had in place a 1.6x Barlow for 99x Sirius B was a clear white dot.  Its brightness matched

well its stated magnitude of 8.5.  It was a very small point but reasonably bright.  It was the only star near Sirius. 

I was pleased to confirm the sighting and noted  Sirius B did not jump around at this lower magnification.




22:20 PST

I was now having trouble with the 13mm EP fogging up too.  I could clear the field lens with my glove but

within a few seconds of my eye being against the EP it would fog up again.  When this happened, another

- what appeared to a diffraction spike - appeared making the view less clear and quite murky.  I could no

longer detect Sirius B.  Then a bright point appeared in the lower right diffraction spike!  This was clear and

persistent but made no sense with the earlier 100% certain observation of B at 1 O'Clock position.




Observing Factors:

I noted that Sirius was now directly above a very bright street light.  There were several neighbours exterior lights

spilling light onto me from several directions.  Behind and above me were the unshielded interior '5 light fixture' of my

neighbours upstairs dining room light!  My glasses were removed which would have limited the most obvious

source of reflections.  Despite being 100% certain of my earlier sighting (and by 'certain' I mean certain that I

observed a star at a particular position), I was now beginning to doubt what I had seen.  I had even

confirmed the earlier sighting at different powers and with different EP's.  I continued observing for another

20 minutes during which time I could not detect Sirius B again.



Conclusions:

Considering this observing session as a whole, I felt the sighting of a star close to Sirius at the 1 O'Clock position

with the 13mm Ultima Lx EP at 99x was the best quality observation.  The star was steady and its brightness consistent

with B's 8.5 magnitude.  The deciding factor will have to be the photos!  Was there a star at that position?

Was Sirius B at that position?










Sirius B is at the 10 O'Clock Position.

this view is inverted compared to my

my view at the eyepiece





This image of Sirius more closely resembles the

appearance of the stars visually.







Sympathy for Lovell


I now have sympathy for Lovell (Mars, Canals, Vegetation - but lets not forget also a brilliant Astronomer). 

Despite being very careful I have never seen so many 'here one minute, gone the next' points of lights,

reflections, and fleeting glimpses.  A couple of nights later while viewing Sirius again, I watched an object

cruise slowly past the field stars, with an almost matching brightness.  I had to rub my eyes to be

sure it really was moving.  And it was - a satellite at high orbit most likely.


Thank goodness for DSLR's.  Its clear my Sirius B was not the real Sirius B!

The star I was observing, I believe was the star at the 7 O'Clock position.

Remember things are much clearer on the images than they were through the eyepiece.


I will have to try again.  Next time I will go out armed with Sirius B's real position

relative to the field stars.  I think the chances of seeing it without knowing where it is

are very slim.  I also think I will need exceptional or unusual conditions to visually

detect Sirius B in an 8" scope - despite stories of people with 3" refractors seeing it!

Another great night under the stars!







Location: West Sechelt

Time: 20:00 hrs - 23:10 hrs PST

Temp: -1 C

Sky: Thin high cloud


Equipment: Astro-Tech AT8IN - 8" Imaging Newtonian

Camera: Nikon D5000 DSLR


Eyepieces:

Celestron Ultima LX - 13mm 2" - 70 AFOV

Antares 4.3mm W70 - 70 AFOV

Antares 1.6x 2" Barlow






Hunting for Sirius B

(taken a few nights previous)




Orion, Taurus and The Pleiades above the scope.

Sirius is above the EZ Finder to the left.







Finally my first contribution to science - other than my

voluntary doughnut and sausage testing program.



This chart is used to work out the real position angle of a

double star when viewing with a Newtonian Telescope.

Simply note the clock position of the double while at the

telescope - then later convert this to the real position angle

using the appropriate diagram.  If it works for you

feel free to download it.




All Content Copyright © James MacWilliam