Alcor and Mizar, were the first binary stars -- a pair of stars that orbit each other -- ever known. Now, astronomers have made the surprise discovery that Alcor is also actually two stars, and is ...

New observations of Alcor, one of the stars that makes the constellation known as the Big Dipper's, have uncovered a smaller companion star named Alcor B. Project 1640 was able to show that the two ...

The second star to the end of the Big Dipper’s handle is called Mizar. Look closely, and you’ll see another fainter star, called Alcor, right next to it. Tonight, find the Big Dipper, known as the ...

If you can only spot one constellation, it's probably the Big Dipper. Other than being easily recognizable, the Big Dipper is special because it contains one of the first known binary star systems.

In ancient times, people with exceptional vision discovered that one of the brightest stars in the Big Dipper was, in fact, two stars so close together that most people cannot distinguish them. The ...

The 2 outermost stars in the Bowl of the Big Dipper always point to Polaris, the North Star. Tonight, notice the two outer stars in the bowl of the Big Dipper – Dubhe and Merak. They always point to ...