03/14/61 Interview with Dr. Harlow Shapley, one of the worlds foremost astronomers
Great Debate (astronomy) - Video Learning - WizScience.com
American astronomer Harlow Shapley was born. He measured the size of Milky Way Galaxy using the signal of variable stars. After that he calculated the position of the Sun within it. Shapley also described a belt around a star, in which liquid water (and therefore life as we know it) can exist. Today this belt is called the habitable zone.