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Klein, Hermann Joseph

Klein, Hermann Joseph

(b. Cologne, Germany, 14 September 1844; d. Cologne, 1 July 1914)


Klein’s scientific curiosity was first aroused by the changing patterns of cloud cover over the Rhine Valley. From studies of the weather he branched out into observational astronomy, spending considerable time looking for changes in surface features of the moon.

In the course of an early career as a bookdealer in Cologne, Klein met Eduard Heis, professor of mathematics and astronomy in Münster and editor of the Wochenschrift für Astronomie, Meteorologie und Geographie from 1857 to 1875. Under Heis’s tutelage, Klein obtained the necessary background in mathematics and astronomy to become a doctoral candidate at the University of Giessen. Here he was granted a Ph.D. in 1874, with a dissertation on the size and shape of the earth. He had already published a number of brief papers, based on astronomical work done in his own private observatory in Cologne; the first such, in 1867, dealt with lunar creater Linné.

In 1879 Klein reported the discovery of a newly formed crater near the Hyginus rille, which became known as Hyginus n (N for Nova). And in 1882 he described a bright flash he had seen, close to another rille inside the crater Alphonsus. These and other observations convinced Klein that at least some of the circular lunar structures referred to as craters had resulted from vulcanism, which process he believed was still occurring on the moon. Volcanic activity inside Alphonsus was confirmed in 1958 by the Russian astronomer Kozyrev. More recently Klein’s viewpoint seems to have been verified by manned exploration of the moon.

In 1880 Klein became director of a combined meteorological and astronomical observatory located in Lindenthal, a western suburb of Cologne, and sponsored by the newspaper Kölnischen Zeitung.Here he continued writing, observing the moon, and studying cirrus clouds for the rest of his life. In 1882 he began editing Sirius, a semipopular astronomical journal. He also wrote a number of books that were widely read throughout Europe and the United States, making him one of the foremost popularizers of meteorology and astronomy of his day.

A lunar crater, formerly known as Albategnius A, was renamed Klein in his honor.


I. Original Works. Klein’s article “Ueber den Mondcrater Linne” appeared in Astronomische Nachrichten, 69 (1867), cols. 35-36; his discovery of Hyginus N was reported in “Ueber die Neubildungen beim Hyginus auf dem Monde,” ibid., 95 (1879), cols. 297-300. His account of a bright flash inside Alphonsus is included, with a half tone illustration, in “über eine vulcanische Formationen auf dem Monde,” in Petermanns geographische Mitteilungen, 28 (1882), 207-210.

Klein wrote his first book on meteorology when he was twenty-one years old: it was Wetterpropheten und Wetterprophezeiung (Neuwied, 1865). His first study of cirrus clouds was “Ueber die Periodicitāt der Cirruswolken,” in Zeitschrift für Meteorologie (Vienna), 7 (1872), 209-212; an overall account of his observations and conclusions appeared in two articles entitled “Cirrus-Studien,” in Meteorologische Zeitschrift, 18 (1901), 157-172, and 23 (1906), 67-82.

Poggendorff, III (Leipzig, 1898), 723-724; IV (Leipzig, 1904), 756; and V (Leipzig, 1926), 636, lists a total of twenty-four articles by Klein and twenty-four books. Notable among the latter are Anleitung zur Durchmusterung des Himmels, 2nd ed. (Brunswick, 1882); Astronomischen Abende 6th ed. (Leipzig, 1905); Allgemeine Witterungskunde, 2nd ed. (Leipzig, 1905); Star Atlas, new ed. with 18 charts (New York, 1910), a translation of Sternatlas (Leipzig, 1886); and Allgemeinverstandlische Astronomie 10th ed. (Leipzig, 1911).

II. Secondary Works. An obituary notice on Klein. written by Hans hermann Kritzinger, appeared in Astronomische Nachrichten, 199 (1914), cols. 15-16. Other details about his life can be found in Poggendoff (see above), and in Meyers grosses Konversations-Lexikon, 6th ed., XI (Leipzig, 1905), 114.

The lunar crater Klein is described in H. Percy Wilkins and Patrick Moore, The Moon (London, 1955), p. 143. The spectroscopic detection of transient gases over Alphonsus is described by Nikolai A. Kozyrev in “Observations of a Volcanic process on the Moon,” in Sky and Telescope, 18 (1958-1959), 184-186, translated by Luigi G. Jacchia.

Sally H. Dieke

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