Ursa Major is one of the most recognizable constellations in the northern sky. The tail end of the constellation is called by our American cousins the Big Dipper because it looks just like a huge water ladle in the sky. This picture was taken with a Camedia C2040 without the use of a scope (I had to wait until 3 in the morning to take this picture as the bloody neighbours had all their bloody lights on all night until 3 and it was polluting my views). The star in the middle of the 'handle' is called and if you look really carefully (without telescopes or binoculars), you might even see two stars. That's because there is a second much fainter star called Alcor. The ability to resolve the two stars with the naked eye is often quoted as a test of eyesight - if you can't see two stars, you probably need glasses!
Okay, time to use the telescope now, with a Neximage CCD imager and magnification equivalent to a 6mm eyepiece. The two stars can be clearly seen now. They are about 1.1 light years apart (that's 6,500,000,000,000 miles!) but are what's called a true binary system - that is, they orbit around one another. But that's not at all. Mizar (on the right) may look like one star but it's actually two - Mizar A and Mizar B. Mizar A is closer in the foreground and shines so brightly that's its luminance blocks out Mizar B, which is slightly behind it.
Let's take a closer look at Mizar. Stick on a 3X Barlow lens to the CCD imager and all is revealed - a binary star system within another binary star system. Mizar A is the larger star that we see in the foregound. Not only that - stereoscopic studies have shown that Mizar A actually has another companion star that, unfortunately, is too close to it to resolve with any earth-bound telescope.
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