Using more than 100 spectacular images from the Hubble Space Telescope, Cosmic Butterflies explores the beauty of the most mysterious celestial objects in space, planetary nebulae. The mystery begins at the end of the star's life, when 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. These newly formed, effervescent structures are complemented by a kaleidoscope of colors emitted by glowing gases. Hovering in the gossamer of delicate streamers, the production of planetary nebula by a star is both its most momentous event and foretells its doom when its central energy runs out. In this extraordinary book, Sun Kwok, a leading international expert on planetary nebulae, details the discovery process of the creation of planetary nebulae and of the future of the Earth's Sun. Sun Kwok is Professor of Astronomy at the University of Calgary and a Canada Council Killam Fellow. His book The Origin and Evolution of Planetary Nebulae (Cambridge, 2000) is widely considered to be the definitive treatise on the subject. He serves as chairman of the Planetary Nebulae Working Group of the International Astronomical Union and has been a member of the Advisory Panel of the Institute of Astronomy and Astrophysics since 1993.