How do scientists use the Sun’s spectrum to identify its chemical elements?

Scientists identify the chemical elements in the Sun by analyzing its spectrum, which consists of a continuous range of light crossed by numerous dark lines, known as Fraunhofer lines.1

These dark lines are formed when the cooler gases in the Sun’s outer atmosphere absorb specific, characteristic wavelengths of light emerging from the hotter, denser layers below. Because every chemical element has a unique set of internal quantum states, each element absorbs and emits electromagnetic radiation at specific, discrete frequencies.123

By comparing the observed dark lines in the solar spectrum with laboratory data—where the specific absorption patterns of known elements are measured—scientists can identify which elements are present in the Sun. Furthermore, by analyzing the intensity of these spectral lines, researchers can determine the relative abundance of these elements, accounting for factors such as the state of ionization and the temperature of the solar atmosphere. This method is essential, as it allows astronomers to determine the composition of the Sun without requiring direct physical samples.123