The Big Dipper Gains a Star The Big Dipper - part of Ursa Major in astronomy - may be one of the most recognized features of the night sky, but that doesn't mean it can't stand an occasional improvement. A team from New York's American Museum of Natural History, NASA's Jet Propulsion Lab, Caltech, and the University of Cambridge in England reports that Alcor, the bright star that forms the bend in the dipper's "handle," has a dim red dwarf star orbiting it. They've put out this very pretty image, in which Alcor is renamed Alcor A, and its newly-found satellite star is called Alcor B. Click on the image to enlarge. Neil Zimmerman, a Columbia Ph.D. student, spotted it with the 200-inch telescope at Mount Palomar in California (which used to be the world's largest). "No one had reported this object before, and it was very close to Alcor, so we realized it was probably an unknown companion star," said Zimmerman in a statement. He had to wait a hundred days to see if the interloper was, in fact, moving along with Alcor, or just juxtaposed in the sky much farther away. The second observation sealed the deal. The results are reported in the new edition of The Astrophysical Journal. The two Alcors are about 80 light-years from us, and Alcor B takes more than 90 years to complete one orbit of its larger companion. In the meantime, they make for a colorful picture. Image credit: AMNH/Project 1640