WHY SHOULD WE CARE ABOUT HENRIETTA?

So what does all this mean? Essentially, Leavitt measured how stars luminate and pulsate and by using the period of time in which they pulsate, she was able to calculate their distance from each other and Earth. Her discovery, sometimes called "Leavitt's law," gave astronomers the tools to map the universe.
Henrietta’s work led to Hubble’s discovery of the Andromeda galaxy and basically changed the way we think about the universe. Because of Henrietta, astronomers were able to prove that there are other galaxies and universes out there. Thanks Henrietta for opening up the sky!