An astronomer named Hubble discovered "Red shift"
He noticed that when he looked at things that seemed to be farther away the spectrum of objects like stars and galaxies all seemed to be shifted to the red end of the spectrum. Eventually he concluded that this was because that objects more distant had to be moving away from him. This led others to conclude that this was because the Universe was expanding.
He noticed that when he looked at things that seemed to be farther away the spectrum of objects like stars and galaxies all seemed to be shifted to the red end of the spectrum. Eventually he concluded that this was because that objects more distant had to be moving away from him. This led others to conclude that this was because the Universe was expanding.
