Get Your Universe On!
Because we're all space cadets, at heart.
|Our Previous Night Out|
|Date:||Sunday September 13 2015|
|Conditions:||Clear, light breeze, 13 degrees|
|Theme:||Mizar and Company|
What Does the Big Dipper have in common with Tim Horton's?
OK, you're looking at the big dipper, in the northwestern sky. If you live in a city, then most of the fainter stars will be missing. If you can't see the constellation, put your mouse here. Tonight we talked about the dipper's astonishing secret: Mizar, at the bend in the dipper's handle (put your mouse here to see Mizar). Now take a good, close look at Mizar. It's TWO stars! The little star is Alcor, and has long been considered a vision test of sorts; if you can see Alcor without optical aid, then your eyes are still OK. Mizar and Alcor therefore appear to be a binary, or 2-star system. Things get strange, though, when you look through our scope at this "pair" of stars.
Here's how it looked in our 10-inch scope tonight:
But look: Mizar is itself a close double-- Mizar A and B-- too close together to see with the naked eye. It gets even weirder: amazingly, it turns out that Mizar A, Mizar B and Alcor are all double stars themselves. So the star at the bend of the dipper's handle is actually SIX stars! Alcor is a double star, but we call Mizar the Tim Horton's star, because it's a double-double!