色球或色球层（字义就是有颜色的球）是太阳大气层主要三层的第二层，厚度大约2,000公里，位于光球层的上方和过渡区的下方。

色球层的密度相当低，它起始处，也就是色球层的底部，密度只有光球的10倍；相较于地球的大气层，更只有10。这使得它通常无法看见，只有在日全食的短暂时间可以看见它展现出略带红色的色调，颜色介于红色和粉红色之间。 然而，若没有特殊的设备，因为光球层压倒性的明亮效果，通常是无法看见色球层。

色球层的密度随着与太阳中心的距离增加而降低，从每立方公分10颗微粒呈指数下降，或从大约1.6×10 kg/m到最外的边界处为2×10 kg/m。温度从内侧边界6,000K到最低处大约是 3,800K，然后向外增加至外侧与日冕过渡区交界处的温度大约是35,000K。 图1.呈现色球层的温度和密度随距离变化呈现的趋势。

The chromosphere (literally, "sphere of color") is the second of the three main layers in the Sun's atmosphere and is roughly 2,000 kilometers deep. It sits just above the photosphere and just below the solar transition region.

The density of the chromosphere is very low being only 10 times that of the photosphere, the layer just below it, and 10 times that of the atmosphere of Earth. This makes the chromosphere normally invisible and it can be seen only during a total eclipse, where its reddish color is revealed. The color hues are anywhere between pink and red. However, without special equipment, the chromosphere cannot normally be seen due to the overwhelming brightness of the photosphere.