What fundamental system of measurement relies on the Cepheid variable technique as its first rung?
Answer
Cosmic distance ladder
The successful deployment of Cepheid variables to measure the distance to Andromeda established the fundamental first rung of the cosmic distance ladder. This ladder is a series of overlapping techniques used by astronomers to measure increasingly greater distances across the universe. Since Cepheids could be used to measure distances to nearer galaxies, they provided the anchor calibration points necessary to determine the distances to further galaxies using other methods, making the Cepheid technique foundational for mapping the vast expanse of space beyond the local group.
Related Questions
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