Mystery Object?

On 4/3/08 I observed Mizar with my 20x80 Binocs. In-between the two stars, I observed a third object! It is just a little off-center and a little south of the line between Mizar and it’s double. I checked all my star charts and computer programs but none show an object there.

On 4/5/08 I went out and again observed the same object in the same location (just to be sure). Does anyone know what this is? I am cross-posting to “After Dark” and “Deep Sky Observing” forums.

Darryl

Darryl Simmons said:On 4/3/08 I observed Mizar with my 20x80 Binocs. In-between the two stars, I observed a third object! It is just a little off-center and a little south of the line between Mizar and it’s double...Does anyone know what this is?

Since you were observing with 20x80 binoculars, I don't believe you were seeing Mizar and its "double," but that you saw Mizar and Alcor, two stars that are 11.8 arcminutes apart. There is an 8th magnitude star that is more or less between these two that was once named Sidus Ludovicianum. Look at this field with a telescope, and the relationship between these three stars will become obvious; Mizar itself is an easily split -- bright and beautiful -- double separated by about 14.3 arcseconds.

I think Herbert has nailed it for you. Here's a quick clip from Cartes Du Ciel. It Shows Mizar as a double but not cleanly split.

Attached Image: