How Do We Know How Far Away the Stars Are?: Quick Facts

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Diagram illustrating how astronomers calculate the distance to a star using parallax: Earth is shown in two positions on opposite sides of its orbit around the Sun, with lines extending to a nearby star X and further to distant background stars. The apparent shift in star X's position, measured as angle A, is used to determine its distance, with the baseline labeled as 186,000,000 miles.

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Topics

Star Parallax Sun Bellatrix Quasar Supernova Astronomical observatory Constellation Black hole Neutron star The life cycle of a star