Part 5/10:
Several hundred years later, Father Georges Lemaître, a Belgian priest and physicist, expanded the seeds sown by Grosseteste, positing an ever-expanding universe—a notion initially dismissed by contemporaries including Einstein. Observations by astronomer Vesto Melvin Slipher about redshift among galaxies corroborated Lemaître’s theories and revealed an expanding cosmos, culminating in Edwin Hubble's formulation of Hubble's Law.
The law articulates a direct relationship: the further away a galaxy is, the faster it seems to move away from us. This observation has critical implications for cosmology—such as understanding redshifts observed from various galaxies due to the expansion of space itself—not the galaxies moving through space.