The English astronomer Sir William Huggins (1824-1910) pioneered in applying the techniques of spectrum analysis, or spectroscopy, to the study of the stars.
Sir William Huggins
William Huggins was born in London on Feb. 7, 1824, to a family of considerable means. Educated by tutors and under no obligation to earn a living, he occupied his early years with the study of physics, chemistry, and physiology. Only in 1856 did his interests settle on astronomy, and upon building a private observatory during that same year at Tulse Hill, South London, he began making routine types of observations. Then, in 1859, Gustav Kirchhoff and Robert Bunsen published their epochal interpretation of spectral lines, according to which each of the chemical elements emits and absorbs light of various characteristic frequencies. Huggins became one of the small band of astronomers who utilized this discovery to forge a new branch of science—astrophysics.
Much of the early spectroscopy work concerned the sun, whose spectrum displayed numerous dark lines, the significance of which could scarcely be guessed. The analogous spectra of stars were so faint that little more could be done than group them into various types, in the hope (eventually fulfilled) that each type would correspond to a particular type of star, or even a particular phase in an evolutionary cycle of star development. Huggins, however, determined to perfect his instruments to the point of permitting some genuine analysis of stellar spectra. By 1863 he had succeeded to the extent of being able to name some of the chemical constituents of several stars on the basis of numerous stellar emission lines. Similar attempts on comets and planets were less successful, but those on the nebulae were nothing short of spectacular. For about a century these hazy spots of light had been cataloged by the thousands. As telescopes were improved, many nebulae had been resolved into millions of individual stars grouped into what are now termed other galaxies. Whether all nebulae could be so resolved, or whether some of them were something other than a collection of stars, was decided by Huggins in 1864, when he discovered, in the constellation Draco, a bright nebula whose spectrum clearly stamped it a mass of glowing gas.
Interesting as these early findings were, their very novelty militated against appreciation of the real significance of the new tool—spectroscopy. In 1868, however, Huggins established the truly revolutionary character of spectroscopy beyond all doubt. Celestial movements were what astronomers understood, and movements were what he gave them—movements of a kind unobtainable in any other way. By drawing an analogy to the shift of pitch that accompanies a moving source of sound waves (the Doppler effect), he inferred, by measuring a shift in its spectral lines, that the bright star Sirius was moving away from the sun at a rate of 29 miles per second.
Huggins worked until the day of his death, on May 12, 1910, following the lines of research opened in his first decade of spectroscopic inquiry and pioneering in the use of photography. In recognition of his contributions he was knighted (1897), awarded the Order of Merit (1902), and showered with honors from all parts of the scientific world.
Further Reading on Sir William Huggins
The only biography of Huggins is John Montefiore and others, A Sketch of the Life of Sir William Huggins, K. C. B., O. M. (1936), from material collected by Lady Huggins.