At the end of a star's life, it wraps itself in a cocoon by spilling out gas and dust. Sometime later, a butterfly-like nebula emerges from the cocoon and develops into a planetary nebula. Planetary nebulae are among the Most beautiful of the celestial objects imaged by the Hubble Space Telescope. Their structures, like bubbles floating in the void, are complemented by a kaleidoscope of color emitted by glowing gases. Delicate, lace like, streamers of gas add to their complexity. The production of a planetary nebula is a milestone in the 1ife of a star, an event that foretells the doom of the star before it disappears into oblivion. In this book, Sun Kwok tells the story of the discovery process of the creation of planetary nebulae and of the future of the Sun.