Born 19th November 1813 - Died 16th August 1862


Elizabeth, the wife of William Stephen Jacob
Elizabeth, the wife of William Stephen Jacob,
a portrait of William Stephen not yet having been located.


A son of Reverend Stephen Long Jacob, he was born on 19th November 1813, baptized on 26th December of that year and died on 16th August
1862. On 17th September 1844 he married Elizabeth, daughter of Mathew Coates. She was born on 31st December 1819 and died on 8th S
eptember 1898. They had children:

1 Anna, born 29th July 1847. On 3rd September 1882 she married A E Pridham, a solicitor.
2 Philip, Indian Civil Service, born 27th January 1849, dsp 1874.
3 Stephen, Indian Civil Service, born 31st October 1850, died in December 1898.
4 Francis MICE, born 26th April 1853.
5 William Henry, born 21st October 1854, dsp 13th April 1875.
6 George, Indian Civil Service, born 15th October 1857.
7 Charles, born 17th October 1859, died in 1876.
8 Mary, born 14th October 1854. In November 1889 she married the Reverend Arthur Elwin of Dover, Kent.

He was educated at Addiscombe and Chatham, and followed a carreer in the Indian Army. He was lieutenant in the Bombay Engineers 1833-1848 and established a private observatory at Poona in 1842, before becoming Director of the Madras Observatory 1848-1859. He made observations on double stars, on satellites of Saturn and on Jupiter. He was elected a Fellow of the Royal Astronomical Society in 1849 and died at Poonah on 16th August 1862.

Much has been written about his work in the field of astronomy, ever more turning up on the major internet search engines. Below is a paragraph kindly written for this site by the astronomer David Kipping, an expert in the field of exoplanets.

'In the field of astronomy, Captain William S. Jacob is believed to have made the first scientific claim for the detection of a planet outside of our Solar System (an "exoplanet"). This historic paper, published in the Monthly Notices of the Royal Astronomical Society in 1855, argued that observed deviations in the motion of the binary star system 70 Ophiuchi indicated the presence of a perturbing planet. Capt. W. S. Jacob stated: "There is, then, some positive evidence in favour of the existence of a planetary body in connection with this system". It was later shown that the detection was a false positive, most likely because the deviations were caused by the Earth's atmosphere rather than a planet. However, the work is considered as a ground-breaking piece of research because it was the first known application of scientific methods to look for planets light years away. In many ways the work was decades ahead of its time and established the search for exoplanets as a scientific enterprise."

NASA have published a timeline that mentions him. Please follow this link for the year 1855:


A diary compiled by William'a daughters Mary and Anna during a journey to Poona and back, which includes a moving account of William's death, has kindly been made available to this site by George Elwin and Liz Bennett; please click HERE.

The following photograph shows from left to right: Stephen, Francis, Mary, Philip and Anna.

His entry in the Dictionary of National Biography, 1885-1900, Volume 29.

JACOB, WILLIAM STEPHEN (1813–1862), astronomer, sixth son of Stephen Long Jacob (1764–1851), vicar of Woolavington, Somerset, brother of John Jacob (1812–1858) [q. v.], and cousin of Sir George le Grand Jacob [q. v.], was born at his father's vicarage on 19 Nov. 1813. He entered the East India Company's college at Addiscombe as a cadet in 1828, passed for the engineers, and completed his military education at Chatham. For some years after his arrival at Bombay in 1831 he was engaged on the survey of the north-west provinces, and established a private observatory at Poonah in 1842. In 1843 he came to England on furlough, married in 1844, and returned in 1845 to India, but withdrew from the company's service on attaining the rank of captain in the Bombay engineers. He now devoted himself to scientific pursuits, and presented to the Royal Astronomical Society in 1848 a catalogue of 244 double stars, observed at Poonah with a 5-foot Dollond's equatoreal (Memoirs, xvii. 79). For several noted binaries he computed orbits (ib. xvi. 320), and the triplicity of v Scorpii was discovered by him in 1847 (Monthly Notices, xix. 322). Appointed in December 1848 director of the Madras Observatory, he published in the ‘Madras Observations’ for 1848–52 a ‘Subsidiary Catalogue of 1,440 Stars selected from the British Association Catalogue.’ His re-observation of 317 stars from the same collection in 1853–7 showed that large proper motions had been erroneously attributed to them (Mem. Royal Astr. Soc. xxviii. 1). The instruments employed were a 5-foot transit and a 4-foot mural circle, both by Dollond. The same volume contained 998 measures of 250 double stars made with an equatoreal of 6.3 inches aperture constructed for Jacob by Lerebours in 1850. Attempted determinations of stellar parallax gave only the ostensible result of a parallax of 0?.06 for a Herculis (ib. p. 44; Monthly Notices, xx. 252). From his measures of the Saturnian and Jovian systems, printed at the expense of the Indian government (Mem. Royal Astr. Soc. vol. xxviii.), he deduced elements for the satellites of Saturn and a corrected mass for Jupiter (Monthly Notices, xvii. 255, xviii. 1, 29); and he noticed in 1852, almost simultaneously with Lassell, the transparency of Saturn's dusky ring (ib. xiii. 240). His planetary observations were reduced by Breen in 1861 (Mem. Royal Astr. Soc. xxxi. 83).

The climate of Madras disagreed with him; he was at home on sick leave in 1854–5, and again in 1858–9. A transit-circle by Simms, modelled on though smaller than that at Greenwich, arrived from England in March 1858, a month before he finally quitted the observatory, of which he resigned the charge on 13 Oct. 1859. He joined the official expedition to Spain to observe the total solar eclipse of 18 July 1860 (Edinburgh New Phil. Journal, xiii. 1). His project of erecting a mountain observatory at Poonah five thousand feet above the sea was favourably received, and parliament voted, in 1862, 1,000l. towards its equipment. He engaged to work there for three years with a 9-inch equatoreal, purchased by himself from Lerebours, and landed at Bombay on 8 Aug., but died on reaching Poonah on 16 Aug. 1862, in his forty-ninth year. His wife, Elizabeth, fourth daughter of Mathew Coates, esq., of Gainsborough, survived him. By her he had six sons and two daughters (JACOB and GLASCOTT, Hist. and Genealogical Narrative of the Families of Jacob, privately printed, p. 22).
Jacob's high moral and mental qualities and earnest piety won him universal esteem. He was elected a fellow of the Royal Astronomical Society in 1849. The results of magnetical observations at Madras (1846–1850) were published by Jacob in 1854; those made under his superintendence (1851– 1855) by Mr. Pogson in 1884. Jacob published in 1850 the Singapore meteorological observations (1841–5), and in 1857 those at Dodabetta (1851–5). While in England in 1855 he wrote on the ‘Plurality of Worlds,’ and described his computation of stellar orbits for the Royal Astronomical Society (Monthly Notices, xv. 205).
[Monthly Notices, xxiii. 128; Mémoires Couronnés par l'Académie de Bruxelles, XXIII. ii. 129, 1873 (Mailly); André et Rayet's L'Astronomie Pratique, ii. 84.]





WilliamH. George, © 2001, Edward Jacob (1713-1788), A Biography, ISBN 0 9534092 3 6.
Sir Bernard Burke, Ulster King of Arms, 'A Selection of Arms Authorised by the Laws of Heraldry', London 1860.
MSS in the possession of Margaret Hyatt-Jacob
Pedigree of Jacob Family registered at the College of Arms
Pedigree of Jacob Family published anon in ca 1840.
Information supplied by Edward Crawford.
Information supplied by George Elwin.
Photographs supplied by George Elwin.
Boase, 1797, p 43.


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