Dictionary of National Biography, 1885-1900/Goodricke, John
GOODRICKE, JOHN (1764–1786), astronomer, born at Groningen on 17 Sept. 1764, was the eldest child of Henry Goodricke of York, by his wife, Levina Benjamina, daughter of Peter Sessler of Namur; and on his father's death, 9 July 1784, became heir to his grandfather, Sir John Goodricke of Ribston Hall in Yorkshire, who, however, survived him. Goodricke earned lasting distinction by his investigations of variable stars. At the age of eighteen he discovered the period and law of Algol's changes. He first saw the star lose light on 12 Nov. 1782, and observed it at York every fine night from 28 Dec. to 12 May. The results were communicated to the Royal Society in a paper entitled ‘A Series of Observations on and a Discovery of the Period of the Variations of the Light of the Bright Star in the Head of Medusa, called Algol’ (Phil. Trans. lxxiii. 484); and in a supplement, ‘On the Periods of the Changes of Light in the Star Algol’ (ib. lxxiv. 287). His suggested explanation of the phenomenon by the interposition of a large dark satellite still finds favour. The merit of the research was recognised by the bestowal of the Copley medal in 1783.
His discoveries of the variability respectively of β Lyræ and of δ Cephei dated from 10 Sept. and 19 Oct. 1784 (ib. lxxv. 153, lxxvi. 48). He perceived the double periodicity of the former star in 12d 19h, a determination regarded by him as merely provisional (Schönfeld's period is nearly three hours longer), and accounted for the observed changes by the rotation on an axis considerably inclined to the earth's orbit of a bright body mottled with several large dark spots. For δ Cephei he gave a period of 5d 8h 37½m (10m too short), remarking that such inquiries ‘may probably lead to some better knowledge of the fixed stars, especially of their constitution and the cause of their remarkable changes.’ Goodricke died at York, in his twenty-second year, on 20 April 1786, and was buried in a new family vault at Hunsingore, Yorkshire. A portrait of him exists at Gilling Castle in the same county. He was unmarried, and was elected a fellow of the Royal Society fourteen days before his death.
[C. A. Goodricke's History of the Goodricke Family, p. 38; Gent. Mag. vol. lvi. pt. i. p. 353; Poggendorff's Biog. Lit. Handwörterbuch; Lalande's Bibl. Astr. p. 587; Watt's Bibl. Brit.]