What is the critical vulnerability affecting the entire Cosmic Distance Ladder structure?

Answer

Systematic error accumulation where errors in lower rungs magnify higher up.

Since each rung calibrates the next, any small systematic error made when measuring a lower rung, such as Cepheid distances, is magnified as that measurement is used to anchor the calibration of the next, farther rung.

What is the critical vulnerability affecting the entire Cosmic Distance Ladder structure?

#Videos

How Do We Measure Distance In The Universe? - YouTube

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