| Term | Definition |
|---|---|
| nuclear fusion | The combining of two atomic nuclei into a single larger nucleus, as when two hydrogen atoms join together to form helium. |
| core | The central part of the sun, where nuclear fusion occurs. |
| photosphere | The inner layer of the sun’s atmosphere |
| chromosphere | The middle layer of the sun’s atmosphere |
| corona | The outer layer of the sun’s atmosphere |
| prominence | A loop of gas that protrudes from the sun’s surface, linking parts of sunspot regions. |
| solar wind | A stream of electrically charged particles produced by the sun’s corona |
| sunspot | Dark, cooler regions on the surface of the sun |
| solar flare | An explosion of hydrogen gas from the sun’s surface that occurs when loops in sunspot regions suddenly connect |
