Who first calibrated the Cepheid variable stars for use in determining distance?

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Henrietta Leavitt first calibrated Cepheid variable stars in the early 20th century while working at the Harvard College Observatory. Her work allowed astronomers to use Cepheids as standard candles for measuring distances in the universe. Henrietta Leavitt first calibrated the Cepheid variable stars while working at the Harvard College Observatory in the early 1900s. Her work allowed for the use of Cepheid variables as a standard candle for determining distances in the universe.

Who First Calibrated the Cepheid Variable Stars for Use in Determining