Shapley, Harlow (1885-1972) -- from Eric Weisstein's World of Scientific Biography

American astronomer who discovered the galactic distance scale using RR Lyrae

in 1918. He looked at variables in globular clusters,

noticed that they were spherically arranged about a point 20 kiloparsecs away, which he correctly identified as the center of the galaxy

(although the true distance, corrected for interstellar extinction, in 10 kpc). He extrapolated distances to the Large Magellanic Cloud

by observing RR Lyrae

and Cepheid Variables.

All were assumed to lie at the same distance, and he obtained their distances using parallax measurements. He published a catalog of bright galaxies

in 1932 with Adelaide Ames, showing that nearby galaxies

are not uniformly distributed.

de Vaucouleurs, G. and de Vaucouleurs, A. Reference Catalog of Bright Galaxies, Being the Harvard Survey of Galaxies Brighter than the 13th Magnitude of H. Shapley and A. Ames, Revised, Corrected, and Enlarged with Notes, Bibliography, and Appendices. Austin, TX: University of Texas Press, 1964.

Shapley, H. Flights from Chaos: A Survey of Material Systems from Atoms to Galaxies. New York: McGraw-Hill, 1923.

Shapley, H. (Ed.). Source Book in Astronomy 1900-1950. Cambridge, MA: Harvard University Press, 1960.