Assertion: andromeda galaxy's star | /r/CapableOf | serve as a milepost marker."hubble
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text: Edwin Hubble measured its vast distance by uncovering a variable star that served as a "milepost marker."Hubble went on to discover the expanding universe where galaxies are rushing away from us, but it has long been known that M31 is moving toward the Milky Way at about 250,000 miles per hour.