Dictionary of National Biography, 1885-1900/Pigott, Edward
PIGOTT, EDWARD (fl. 1768–1807), astronomer, was the son, probably the eldest son, of Nathaniel Pigott [q. v.] of Whitton, Middlesex. The phenomena of Jupiter's satellites were observed by him with a view to longitude-determinations from 1768; and he watched, at a station near Caen, the transit of Venus of 3 June 1769. He aided his father's geodetical operations in Flanders in 1772, and surveyed the country near the mouth of the Severn in 1778–9 (Phil. Trans. lxxx. 385). On 23 March 1779 he discovered at Frampton House, Glamorganshire, a nebula in Coma Berenices (ib. lxxi. 82), and at York, on 22 Nov. 1783, the comet which bears his name (ib. lxxiv. 20, 460). But although its period has since been computed at 5.8 years, it has not reappeared. His deaf and dumb friend John Goodricke [q. v.] co-operated with him in observing it.
The variability in light of η Aquilæ was detected by Pigott on 10 Sept. 1784, and on 5 Dec. he assigned to its changes a period (about 26 minutes too long) of 7 days 4 hours 38 minutes (ib. lxxv. 127). He also essayed the establishment of an artificial system of photometry. A catalogue of fifty variable or suspected stars was published by him in 1786 (ib. lxxvi. 189), with the remark that ‘these discoveries may, at some future period, throw fresh light on astronomy.’ In a paper on the geographical co-ordinates of York he gave, in the same year, the first practical application of the method of longitudes by lunar transits, independently struck out by him (ib. p. 409). On 3 May 1786 he observed the transit of Mercury at Louvain (ib. p. 389), and after his return to England sent to the Royal Society an account of an auroral display viewed at Kensington on 23 Feb. 1789 (ib. lxxx. 47). His next residence was apparently at Bath, where he discovered the fluctuations of R Coronæ and R Scuti (ib. lxxxvii. 133). Six years later he gave a further discussion, from fresh materials, of the latter star's period (ib. xcv. 131). The conclusion of this paper was written at Fontainebleau in 1803. In it he strove to account for the observed irregular waxings and wanings of stellar brightness by the rotation of globes illuminated in patches. He inferred, moreover, the existence of multitudes of ‘dark stars,’ and surmised that the ‘coal-sacks’ in the Milky Way might be due to their aggregations. Pigott is said by Mädler to have been an early observer of the great comet of 1807. This is the last we hear of him.
[Watt's Bibl. Brit.; Mädler's Geschichte der Astronomie, ii. 21, 265; Berliner astr. Jahrbuch, 1782 p. 146, 1788 p. 161; cf. Herschel's Memoir of Caroline Herschel, 1876, p. 103.]