Cat's-eye nebula(NGC 6543) A complex planetary nebula lying at a distance of about 1 kiloparsec in the constellation Draco. It represents the final stages in the life of an ordinary star. As it dies, the star blows off shells of glowing gas. The structure of this nebula appears to be so intricate, showing high-speed gas jets and unusual knots of gas as well as concentric gas shells, that some astronomers have theorized that the central star may be a binary.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006