Harvard University Clock Tower - the school at which Leavitt did her research.
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Courtesy of Corel Photography

Henrietta Swan Leavitt

Henrietta Swan Leavitt was born in Massachusetts in 1868. She became interested in astronomy in college. Unfortunately, she got sick after her graduation from college. She did recover from her sickness, though it did leave her almost completely deaf. But she hadn't forgotten astronomy!

Henrietta started working at Harvard's Observatory for 30 cents an hour. She observed stars and watched how variable stars changed in brightness. Henrietta is known for her discovery of a type of variable stars named cepheid variables. Cepheid variables are stars that go through cycles of brightness and darkness. Henrietta found that when observing a cepheid variable, she could relate the length of the brightness cycle to the size of the star. With this discovery, she was able to determine the distances between stars and the Earth.

She died of cancer in 1921 at age fifty-three. Her name was given to a crater of the moon to honor deaf men and women who have worked as astronomers.

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