Spectroscopy
The analysis of light spectra to determine the composition and properties of matter.
Also: spectrum analysis
Definition
Spectroscopy is the study of the interaction between matter and electromagnetic radiation across a range of wavelengths. In astronomy, spectroscopy analyzes the light from stars and galaxies to determine their chemical composition, temperature, velocity, density, and magnetic field. Each element absorbs or emits light at characteristic wavelengths (spectral lines), acting as a unique fingerprint.
Example
“By analyzing the spectrum of a distant star, astronomers can identify the dark absorption lines of hydrogen, helium, and iron, determine the star's surface temperature from its peak emission wavelength, and measure its recession velocity from the redshift of these lines.”
Synonyms
- spectrum analysis
- light spectrum analysis
- spectral analysis