Simplified picture of the Carbon-Nitrogen-Oxygen fusion cycle
University of Oregon

The Carbon-Nitrogen-Oxygen Fusion Cycle

When the temperature of the core of a star reaches about 16 million kelvins (that's REALLY hot!), the production of Helium occurs through another fusion cycle. This cycle is named the Carbon-Nitrogen-Oxygen (CNO) cycle. Here Carbon gets the cycle going, but it is not used up.

Watching the movie below may help you to visualize this process.

Last modified May 10, 2010 by Randy Russell.

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