Example: When I am using Skysafari Pro it shows: Mizar A 0.8”. When I go to the info page it lists: Separation 0.8” at 214.9 degrees. I would assume this means that Alcor is .8 arc seconds away and located at 214 degrees right declension. But when I read the accompanying notes they say Mizar and Alcor are separated by 11.8” So I seem to have something wrong and have not been able to find any explanation. If someone could enlighten me I would appreciate it. If the 0.8” is not the separation distance between Mizar and Alcor, what is it? And why does a similar designation show up for most double stars (ie: Kochab 214.1”). Thanks!
SkySafari Pro nomenclature question
Posted 08 June 2021 - 03:36 PM
Looks like the description is saying the separation of 11.8” is between Mizar and Alcor, whereas the info page is saying the separation of 0.8” is between Mizar A and Mizar B. Mizar by itself, without Alcor, is a double star system.
- Bean614 likes this
Posted 08 June 2021 - 03:52 PM
That is possible, but further down in the notes it indicates that Mizar A and B are 14” apart. At least that is how I read it. You are probably right that the separation listed is between A and B even though most of the discussion is about Mizar and Alcor. The discussion is certainly not clear, at least to me, and makes me wonder if I am off track somewhere.
Posted 08 June 2021 - 04:29 PM
Is it 11.8" (arc-sec) or 11.8' (arc-min)?
SS6 Pro says the latter.
From what I read:
Mizar A and B (not Alcor) have 14" (arc-sec) separation. Each of them are binaries (Aa Ab Ba Bb).
I am guessing Sky Safari says the Mizar A double is actually Mizar Aa and Ab have 0.8" (arc-sec) separation.
Posted 08 June 2021 - 06:55 PM
That sounds correct. I miss typed 11.8” instead of 11.8’. That should be Mizar A and Alcor. The 14” is probably Mizar A and B and the 0.8” Mizar Aa and Ab. Seems I read that Alcor may also have a double as well, a complicated little group. I think that clears it up in my mind and will give me a clearer idea of what to look for. Looks like the best I can hope for with my scopes is to see Mizar A and Alcor with maybe Mizar B on a clear night. Thanks!
Posted 08 June 2021 - 10:30 PM