Spectroscopy: Unlocking the Secrets of Starlight

Spectroscopy splits light into a rainbow of colors, revealing hidden details.
Each chemical element leaves unique “fingerprints” in the form of spectral lines.
Astronomers use it to determine a star’s composition, temperature, and motion.
Doppler shifts in spectra show whether stars and galaxies are moving toward or away from us.
Cecilia Payne used spectroscopy in 1925 to prove stars are mostly hydrogen and helium.
It helps discover exoplanets by detecting tiny wobbles in a star’s spectrum.
Spectroscopy reveals galaxies are receding, providing evidence for the expanding universe.
It also measures the atmospheres of exoplanets for gases like oxygen and methane.
Different types—optical, infrared, ultraviolet, X-ray—unlock different cosmic secrets.
Spectroscopy turns starlight into a cosmic barcode, decoding the universe’s story.