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Modern astronomers use parallax to determine the distance to a star. Parallax is based on the stars of the stellar universe that are stationary where the change in the angular position of a stationary star is measured after the observed on the earth propagates the distance of the earth's orbital diameter (six months) but the distance to a 4.22 light year (4 x 10^16 meters) star is more than 10^7 times larger than the earth's orbital diameter (1.4 x 10^10 m); consequently, the parallax reference distance of the earth's orbital distance is to short of a distance to produce a change in the angular position of a stationary 4.22 ly star using the Hubble that has a resolution of .1 arcsec.