AST-1002 Chapter Notes - Chapter 10: Solar Wind, Chromosphere, Photosphere
Document Summary
Immediately above the photosphere is a dim layer of less dense stellar gas, called the chromosphere ( sphere of color ). This unfortunate name suggests that it is the layer we normally see, but for centuries the chromosphere was visible only when the photosphere was blocked during a total solar eclipse. High-resolution images of the chromosphere reveal numerous spikes, which are jets of gas called spicules. Spicules - a narrow jet of rising gas in the solar chromosphere. Spicules are generally located on the boundaries of enormous regions of rising and falling chromospheric gas called supergranules. Supergranule - a large convective cell in the sun"s chromosphere containing many granules. Just as earth"s gravity prevents most of our atmosphere from escaping into space, so, too, does the sun"s gravity keep most of its outer layers from leaving. Some of the gas is moving fast enough around a million kilometers per hour to escape the sun"s gravity forever and race into space.
