How does red shift from distant galaxies provide evidence for the beginning of the universe?

Redshift from distant galaxies indicates that these galaxies are moving away from us, which suggests that the universe is expanding. This phenomenon is a key piece of evidence supporting the Big Bang theory, as it implies that the universe was once concentrated in a much smaller, hotter state. By measuring the degree of redshift, astronomers can estimate the rate of expansion and extrapolate back to a singular starting point, reinforcing the idea of a beginning to the universe. Thus, redshift provides crucial observational support for the concept of an expanding universe that originated from an initial explosive event.