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10.4: How the Sun Works

Last updated

Jul 23, 2025
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- 10.3: Our Star, the Sun
- 10.5: A “Quick Guide” to Solar Fusion—The Proton-Proton Cycle

Lumen Learning
Lumen Learning

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The sun does not burn. The belief that the sun does burn is a misconception. In stars the size of the sun or smaller, the fusion process is referred to as the proton-proton cycle or proton-proton chain reaction. The general steps to the Proton-proton cycle include:

It takes about 100,000 years for that energy to get from the sun’s core to the photosphere.

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