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Also known as red shift
thumb|upright|Spectral line|Absorption lines in the [[visible spectrum of a supercluster of distant galaxies (right), as compared to absorption lines in the visible spectrum of the Sun (left). Arrows indicate redshift. Wavelength increases up towards the red and beyond (frequency decreases).]]
AI overview
Redshift is the stretching of light waves from distant galaxies, causing their light to shift toward the red end of the spectrum—a shift that scientists can measure by comparing spectral lines to those of nearby objects like the Sun. This phenomenon matters because it helps astronomers determine how far away galaxies are and provides evidence about the expansion of the universe.
AI-generated from the Wikipedia summary — may contain errors.