Respighi, Lorenzo

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RESPIGHI, LORENZO

(b. Cortemaggiore, near Piacenza, Italy, 7 October 1824; d. Rome, Italy, 10 December 1889)

astronomy.

Respighi studied at Parma and at the University of Bologna, where he took his degree in mathematics in 1847. Two years later he was appointed professor of mechanics and hydraulics at the University of Bologna. His first works were purely mathematical, such as the well-known memoir on the principles of differential calculus, which Cauchy presented at the Academy of Sciences in Paris. His interest soon turned to astronomy, and in 1855 he succeeded Calandrelli as director of the astronomical observatory at the University of Bologna. Respighi moved easily from mathematics to observation, and he made an excellent determination of the latitude of the Bologna observatory. At the same time he worked on the reductions and discussion of meteorological and magnetic data accumulated by Calandrelli. In 1860 he published an exhaustive study of the comets observed during the years 1814–1843.

At Calandrelli’s death in 1866, Respighi was appointed professor of astronomy at the University of Rome and was made director of the Campidoglio observatory. Here he devoted himself mainly to studying solar phenomena. During a three-year period he mapped more than 8,000 prominences, and his systematic solar studies continued for more than fifteen years. Especially important are the studies on the spectra of sunspots. He observed the splitting of the absorption lines, which was later explained by Hale as the result of a Zeeman effect of the magnetic field in the sunspots.

Respighi was the first to use the objective prism properly for the observation of stellar spectra. On 15 February 1869 he was able to show the French physicist Cornu excellent stellar spectra by placing a 12 prism in front of the equatorial telescope of the Campidoglio observatory.

Respighi contributed three catalogs to meridian astronomy: one of 285 stars (1877), one of 1,463 stars (1880), and one of 1,004 stars (1884). In the course of this work he also discussed the aberration of light, performing experiments with a water-filled telescope.

Repighi was a member of several Academies, including the Accademia Nazionale dei Lincei, and a foreign member of the Royal Astronomical Society.

BIBLIOGRAPHY

A complete bibliography of Respighi’s paper may be found in the obituary by P. Tacchini, in Memorie della Societa degli spettrocopisti italiani, 18 (1889), 200–203. Accounts of his work are in C. Andre, G. Rayet, and A. Angot, L’astronomie pratique et les observatoires, V, Observatoires d’Italie (Paris, 1878), 82, 150; and M. Cimino, Contributi scientifici dell’Osservatorio astronomico di Roma, ser. 3, no. 25 (1964).

Guglielmo Righini