Question

Explain how cepheid variables are used to
estimate astronomical distances

26 Jun 2018
Answer :
Word Count : 536

Cepheid variables play a crucial role in estimating astronomical distances, providing astronomers with a reliable method to measure the vast distances between celestial objects. These variable stars exhibit regular pulsations in their brightness, and the period of these pulsations is directly related to their intrinsic luminosity. By measuring the apparent brightness of a Cepheid variable and understanding its intrinsic luminosity, astronomers can employ the inverse square law to calculate the distance to the star or galaxy where the Cepheid is located.

1. Period-Luminosity Relationship:
   Cepheid variables follow a well-established relationship between their pulsation period and intrinsic luminosity. Henrietta Leavitt first discovered this relationship in the early 20th century while studying Cepheids in the Small Magellanic Cloud. She found that the period

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