I live at 45 degrees north, so at best Sirius is quite low in my winter sky, and I've never seen its white dwarf companion star through my own scope at this latitude. I know a person who's seen it through a 6-inch f/8 scope from Southern California, so saying I've seen it through a 28-inch scope doesn't seem like much, but it's a big deal for me!
I had just finished observing NGC 2336 and IC 467 two nights ago when the sky became mostly overcast, but there were still some holes in the clouds. The seeing was quite steady so I pointed the scope at Sirius just as it appeared through a clear spot in the clouds. At low power Sirius was a marvelous sight, and I quickly upped the magnification to 408x. To my amazement, Sirius looked still looked sharp, and was surrounded by wavering diffraction rings no less.
Not knowing where to look for Sirius B, I scanned around and to my utter delight quickly found it, just off the northeast diffraction spike - a tiny but definite spark of a star. Woohoo! I couldn't have been more excited! Clouds covered it up too soon, and when the next clearing appeared I was ready with 547x. Sirius B was just as definite, and Sirius A was again a tight ball of incredible brightness surrounded by shimmering diffraction rings. More excitement - I may have done a little happy dance, but there are no witnesses to confirm that report...
Sirius B_invert.jpg
Over the next 30 minutes I chased small openings in the clouds, and had maybe a total of two minutes of sharp views of Sirius B. I discovered it didn't take much atmospheric turbulence to smear the image of this little star into invisibility, which underscored why I had always failed to see it in the past - the seeing needs to be very steady for success. The sky soon became completely overcast and I was finished for the night.
My Cloud (1).jpg
Of course, the forecast was for clear skies all night, and this unwelcome cloud covered only my little portion of Oregon - the rest of the state stayed clear. The red dot in the weather satellite image is my location under the cloud, and the green dot is a friend who enjoyed a full night of clear skies and steady seeing. Even so, this was a memorable night for me, and I'm grateful for finally being to see this tiny white dwarf star in my own scope.
The orientation of my sketch is north down, east to the right. There's a much brighter field star just off the same diffraction spike, but much further away than Sirius B.
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