* Chemical composition: Each element absorbs light at specific wavelengths, creating unique dark lines in the spectrum. By analyzing the pattern and intensity of these lines, astronomers can determine the abundance of different elements present in the star's atmosphere.
* Temperature: The intensity and position of Fraunhofer lines are sensitive to the temperature of the star. Hotter stars have different absorption patterns than cooler stars.
* Velocity: The Doppler shift of the absorption lines reveals whether a star is moving towards or away from Earth. This information is crucial for understanding stellar motions and the dynamics of star systems.
* Magnetic field: Some Fraunhofer lines are sensitive to the presence of magnetic fields. By analyzing the splitting and broadening of these lines, astronomers can study the strength and structure of stellar magnetic fields.
* Pressure and density: The widths and shapes of absorption lines are also affected by the pressure and density of the stellar atmosphere. These parameters can be estimated by analyzing the spectral features.
In essence, Fraunhofer lines provide a detailed fingerprint of a star's physical characteristics, allowing astronomers to understand its composition, temperature, motion, magnetic field, and atmospheric conditions.
