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G. Pietrzyński led a 2013 measurement of the Euclidean distance to the Large Magellanic Cloud using eight late-type eclipsing binaries. The systems contained cool giant stars, whose physical and angular sizes could be compared to infer Euclidean distance.

The study reported approximately $2.2\%$ accuracy and kept statistical and systematic uncertainties separate. Choosing these systems addressed modeling difficulties associated with hotter binaries, while improving an anchor of the cosmic distance ladder and hence the calibration of the Hubble constant.^[ref]

The Large Magellanic Cloud is a nearby galaxy interacting with the Milky Way, containing stars whose independently measurable properties help calibrate astronomical distances. Its proximity makes it possible to combine stellar observations that are much harder to separate in more distant systems.

In a late-type eclipsing binary, orbital velocities and eclipse geometry constrain linear stellar sizes; a surface-brightness calibration supplies corresponding angular sizes. Comparing the two gives a distance anchor rather than assuming one fixed luminosity for every star.^[ref] Such calibration still has systematic uncertainty and samples a galaxy with finite depth.