Photometric Redshift

Photometric redshift is a method used by astronomers to estimate how far away a galaxy is by analyzing its light through different color filters rather than measuring its spectrum in detail. As galaxies move farther away, their light shifts toward the red end of the spectrum due to the universe's expansion—a phenomenon called redshift. By comparing the galaxy's observed colors with models, scientists can determine its approximate distance. This technique is faster and allows astronomers to study many galaxies simultaneously, helping them understand the large-scale structure of the universe and galaxy evolution.