Cosmological Redshift

Cosmological redshift refers to the phenomenon where light from distant galaxies appears shifted toward the red end of the spectrum. This occurs because the universe is expanding, causing the space between galaxies to stretch over time. As light travels through this expanding space, its wavelengths become longer and redder, similar to how the pitch of a siren drops as an ambulance moves away. This redshift helps scientists understand that the universe is expanding and allows them to measure how far away galaxies are, providing crucial insights into the history and evolution of the cosmos.