Shapley, Harlow (1885–1972)
American astronomer who calibrated Henrietta Leavitt's
for Cepheid variables and used
it to determine the distances to globular
clusters. He boldly and correctly argued that the globulars outline
the Milky Way Galaxy in which we live, that
the Galaxy was far larger than had been generally believed, and that it
was centered thousands of light-years away in the direction of Sagittarius.
He was wrong, however, when it came to the nature and distance to the so-called
"spiral nebulae," which we now know to be remote external galaxies. On this
issue, in 1920, he held what was later dubbed astronomy's Great Debate with
Heber Curtis on the scale of the universe.
Shapley graduated from the University of Missouri in his home state, then
wrote an important doctoral dissertation on eclipsing
binary stars under Henry Russell at
Princeton. From 1914 to 1921 he was at Mount
Wilson Observatory, and from 1921 to 1952, he was director of the Harvard
College Observatory, where he did his seminal work on Cepheids, studied
the Magellanic Clouds, and catalogued
galaxies. Together with Adelaide Ames, he published the Shapley-Ames
Catalogue of bright galaxies in 1932. He wrote many books, was an important
popularizer of science, built an outstanding graduate school, and played
a major role in national and international affairs.
Shapley's demonstration that the Sun lay closer to the periphery of the
Galaxy than its center marked another step in the movement away from anthropocentrism
in a cosmological context. During his time at the Harvard Observatory, he
switched from a pessimistic view about the likelihood of extrasolar
planets and life, influenced by the Jeans-Jeffreys
tidal hypothesis, to one of great optimism. His widely-read Of Men
and Stars1 (1958) urges that "millions of planetary systems
exist, and billions is the better word" and that "whenever the physics,
chemistry and climates are right on a planet's surface, life will emerge,
persist and evolve." Shapley also speculated on the possibility that life
might exist on the surface of objects, now known as brown
dwarfs, that are intermediate between planets and stars.
Quote by Harlow Shapley
"Theories crumble, but good observations never fade."
Astronomical objects named after Harlow Shapley include the Shapley
Concentration of galaxies, the planetary nebula Shapley
1, and a crater on the Moon.
Adapted in part from the biographical
entry at The Bruce Medalists website
- Shapley, Harlow. Of Stars and Men. Boston: Beacon Press (1958).