The Sun

Like other stars, the Sun shines by fusing hydrogen into helium in its core. Without the power that this conversion process generates, a star would collapse under its own immense weight. The heavier the star is, the faster it consumes its hydrogen and the sooner it dies. By the time our Sun becomes a senior citizen, most of its hydrogen will be gone and its core will consist of pure helium. With no more hydrogen …

…emits a distinctive deep red color. Scientists often study the chromosphere by filtering out all sunlight except the light that has the wavelength produced by hydrogen in the chromosphere. Corona= is the very hot layer of the solar atmosphere above the chromosphere. It extends to Earth and beyond as the solar wind. The sun's temperature rises to 2 million degrees Celsius at the bottom of the corona, and remains almost that hot as it reaches Earth.