Did I see Sirius B?

[Rahul Zota]

Hi all,

I just bought 10-inch f/4.7 Sky-watcher Dobsonian and I put it to the test this morning before dawn. When I pointed it to Sirius operating at 120x I saw an 8th magnitude star next to it. The main star was showing beautiful four spikes and the fainter star next to Sirius was within the length of the spike. Was this Sirius B? I actually don't know what is the current position and separation of Sirius B. Can anyone help?

[MjrTom]

Sirius B has a magnitude of 8.5 and a separation of 9.4" @ 86.4 degrees

[Rahul Zota]

thanks! I am now confirmed that what I saw was Sirius B!

[MjrTom]

Congrats

[barkis]

You are very fortunate if you saw it against the glare of Sirius, although many amateurs have observed it, and congratulations to you if you have seen it.

Most observers of the Pup need an occulting bar to block the brightness of Sirius itself..

I would repeat your observations to be absolutely certain.

Sirius A & B orbit their common centre of gravity once every 50 years.

Ron.

[Rahul Zota]

Hi Ron, I think I have to make another observation if you say it is difficult to spot it due to the main star's glare. As mentioned in the first reply, Sirius B is 9.4" away from Sirius A at 86.4 degrees. The star I saw was about 8th mag in brightness and was very close to the primary.

[Smeg]

Are you Sirius?

[MjrTom]

Are you Sirius?

Get your coat...

[Rahul Zota]

Finally I have come to know what I saw! It wasn't Sirius B but a ghost image of the bright Sirius!! I knew this when I moved the telescope to the next field. The ghost moved in the different direction than the stars. I then pointed the telescope to Procyon and saw the same thing very close to the star! I was fooled by the ghost!!!

[barkis]

Not to worry Rahul. You must keep trying, perseverence pays off.

I've taken a scan of a picture from Burnhams Celestial Handbook, which will show the difficulty in observing the companion.

Ron.

[West End Wendy]

That's interesting. I wonder if you could use a bahtinov mask for the same purpose as that hexagonal diaphragm.

Now where did I put my 24" refractor...?

[vegaandarctures]

What magnification would be required to spot Sirius B?

[John]

Here is a thread from not to long ago regarding attempts by some SGL members to see Sirius B:

http://stargazerslounge.com/observing-imaging-double-variable-stars/125968-sirius-b.html

I believe it was spotted by some members at this years SGL star party using a 10" Orion Optics maksutov-cassegrain.

From my own (unsuccessful) attempts so far I reckon the trick is to get high magnification (ie: 250x or more) and a very tight star image for Sirius A with the glare from that very tightly controlled or even masked using an occulting device as discussed in the above thread.

It's a really tough challenge I believe.

[michael.h.f.wilkinson]

I have never tried this. I guess the low altitude of Sirius makes it even harder. Still, I might give it a try. I all else fails, I will try to use the 16" RC at the institute.

[Peter Drew]

Your best chance is to look for it at twylight before Sirius gets too bright and swamps it, must be dark enough of course for a star of the magnitude of Sirius B to show.

[michael.h.f.wilkinson]

Your best chance is to look for it at twylight before Sirius gets too bright and swamps it, must be dark enough of course for a star of the magnitude of Sirius B to show.

Good tip, thanks!

[Rahul Zota]

thanks barkis! I can guess how the companion would appear at higher magnification. The picture is very useful.