More Urban Astro - May 31 - Winnipeg

[Kanadalainen]

Ian’s May 31 Report


Locale: My back yard.
Conditions: Average transparency, fair seeing, Bortle 7 suburbia
Equipment: Celestron 80 frac
Time: 10:19 pm to 1:00 am

The day was beautiful – cool and clear. Anticipating some good astro, I released the C80 from its lair and some of my favourite EPs for a quick look around.

Mr. Baar mentioned a certain iconic star (Izar) as a subject of a recent visual observation, and for me this is Mizar A and B, along with Alcor. Whatever is your home position in your brain, quot capita, tot sententiae.

It seems a relatively easy split: Mizar B and Mizar A (actually pairs of stars) but the actual gap between them is in the order of magnitude of something akin to 8 times that of our solar system (30 billion miles). As interstellar distance goes, this might be described as next-door country.

I found out that Mizar and Alcor are 80 lya and share a common proper motion across the sky, and recent data have revealed that Alcor also possesses a dim red dwarf companion, and further, that Alcor is gravitationally bound to Mizar, despite the huge distance between them. Surprisingly Mizar A and B are also doubles – so the system is six stars. No way for me to split them with my little scope, but this knowledge is kind of fun to keep in mind.

Moving my little scope to the deck I could see Jupiter rising, just to the west, Scorpius.

M4 near Antares – Scorpius cossets his riches of globular clusters in the LP suburban skies - to compensate, I looked the biggest of the bunch near Antares. Not and easy catch this evening and at low altitude.

Jupiter – Lovely and fat in the Telrad (yes, I have a Telrad on the C80). Two of the Galilean moons were jumbled close to the East of the planet, with two outriggers to the west. Bands were very apparent so I pushed the mag to 130X and was rewarded with some very clear bands at 1:00 am.

Thanks for reading to the bottom,

Ian

[Kanadalainen]

Here is a rendering of the six star system from a 2015 SandT article.

Ian

[helicon]

Thanks for the report Ian and for explaining the intricacies of Mizar A and B. I hadn't realized that it is a six star system if one includes Alcor. Also, the egyptians considered Mizar to be one of the "indestructibles" along with Kochab because these stars never set. And a perfect destination for the soul of the dead king back in Old Kingdom times.
https://en.wikipedia.org/wiki/The_Indestructibles

[quincy]

Great stuff.
I usually start most of my sessions with Mizar and Alcor. It's been a habit for some time.
It's also fun to jump on and Stelle Doppie, find some quadruple systems and try to split them.

[helicon]

Great stuff.
I usually start most of my sessions with Mizar and Alcor. It's been a habit for some time.
It's also fun to jump on and Stelle Doppie, find some quadruple systems and try to split them.

I usually start with Mizar and Alcor when I star-hop to M101 in the telrad. In my LP sometimes it's visible, sometimes not.

[Bigzmey]

Nice report John! Compared to other bright globs M4 is stronger affected by LP. I remember we berally managed to resolve it for the first time as a large dim spot with my daughter a few years ago. But it is really gourgeous under the dark skies.

[bladekeeper]

Glad you got out, Ian! Some fun spitting!

[John Baars]

Nice observations Ian!
I did not know about the six star system of Alcor and Mizar. Very nice to know. Did you sketch the first image yourself?
Do you know what separation Mizar A and Mizar B separately have?
Nice report, gives one to think about something..

[Kanadalainen]

Nice observations Ian!
I did not know about the six star system of Alcor and Mizar. Very nice to know. Did you sketch the first image yourself?
Do you know what separation Mizar A and Mizar B separately have?
Nice report, gives one to think about something..

.


Hi John,

Those images were picked off the web, I only wish that I did draw it.

I will research the distances, to be sure.

EDIT: Only 8 times the distance of Pluto to the Sun for Mizar B and its little companion. Quite close!

Ian