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It’s often the case that an artist’s work isn’t fully appreciated until after the artist is gone. And the same thing is true in the stars. We appreciate a star’s beauty as it twinkles through the night. But a star’s true glory — a masterpiece of color and form — is also its final creation.
An example is the Cat’s Eye Nebula, in Draco, the dragon. The faint constellation slithers around the north and northeast at nightfall, and moves high across the sky later on.
Photographs of the nebula reveal swirls and loops of green and red — more like a flower than a cat’s eye. But the nebula’s real beauty is not as a photograph, but as a sculpture. It consists of a long bubble of hot gas attached to two bigger bubbles. Jets of gas shoot into space from the tops of the bubbles.
The process that sculpted the Cat’s Eye is the death of its star, which was several times as massive as the Sun. Thousands of years ago, it began throwing off big shells of gas and dust. And about one thousand years ago, it began ejecting its outer layers — a process that eventually will leave nothing but its dead core.
Ultraviolet energy from the core zaps the expanding bubbles, making them glow. And the shape of the nebula may be sculpted by the gravity of a small companion star.
The Cat’s Eye is expanding at hundreds of thousands of miles per hour. Eventually, it’ll spread out so much that it will fade away — and a work of cosmic art will die with its artist.
Script by Damond Benningfield