During the last ten thousand years of a star's life, it goes through a stage called "planetary nebula" phase, during which the star gives off a magnificent display of light. Cotton Candy Nebula is considered a proto-planetary nebulae, beginning this stage.
In the Cotton Candy Nebula we can see a series of concentric rings, representing the "puffs" given off by the star in the last few thousands years of their lives. These "puffs" provide evidence that the star has been "ill" for some time. After a number of these "puffs", the star wraps itself inside a cocoon.
In the Cotton Candy Nebula and the Silkworm Nebula HST images, we are seeing the first indication that the nebulae are emerging from their cocoons, like butterflies undergoing metamorphosis.
Image : NASA Sun Kwok and Kate Su (University of Calgary)
and Bruce Hrivnak (Valparaiso University)