Brown was born in
Hull,
England, the second of four children of William and Emma Brown (née Martin). His father was originally a farmer and later became a timber merchant. His mother and younger brother died of
scarlet fever in 1870, when Brown was not quite 4 years old. He and his two sisters were then looked after by a maiden aunt, until his father remarried five years later.
Education and early career Brown was educated at Totteridge Park School,
Hertfordshire (now part of
Dorset House School) and Hull and East Riding College. After leaving school, he entered
Christ's College,
Cambridge, where he graduated with first-class honours as sixth
Wrangler in mathematics in 1887. He continued with post-graduate studies at Cambridge and worked under the direction of
George Howard Darwin. In the summer of 1888, Darwin suggested that he study the papers of
George William Hill on the
lunar theory. As it turned out, this idea for a line of research was to have a major impact on the remainder of Brown's life. Brown was made a fellow of Christ's College in 1889 and was elected as a Fellow of the
Royal Astronomical Society in the same year. He received his master's degree in 1891 and then left Cambridge to take up a place as a mathematics instructor at
Haverford College,
Pennsylvania. There, he rose rapidly to the position of Professor of Mathematics in 1893. However, he continued most years to return to Cambridge during the summer, often staying with his old tutor, Darwin.
Work on the motion of the Moon At Haverford, Brown continued with his studies of the lunar theory, and made a thorough review of the work of earlier researchers, such as Hill,
de Pontécoulant,
Delaunay and
Hansen. His mastery of the field was shown by the publication of his first great work,
An Introductory Treatise on the Lunar Theory, in 1896, when Brown was still less than 30 years of age. The following year, he was elected as a Fellow of the
Royal Society. Later work has shown this to be true, and astronomers now make a distinction between
Universal Time, which is based on the Earth's rotation, and
Terrestrial Time (formerly
Ephemeris time), which is a uniform measure of the passage of time (see also
ΔT).
Later work and collaborations Brown was an active member of the
American Mathematical Society and served as its president from 1915 to 1916. He retained his professorship at Yale until he retired in 1932. As well as continuing his work on the Moon, he also worked on the motion of the
planets around the
Sun. In 1933, he published the book,
Planetary Theory, co-authored with
Clarence Shook, which contained a detailed exposition of
resonance in planetary orbits and examined the special case of the
Trojan asteroids. In 1937, he was awarded the
Watson Medal by the US
National Academy of Sciences. One of Brown's post-graduate pupils was
Wallace John Eckert, who became an instructor at
Columbia University while finishing his doctorate. Eckert would improve the pace of astronomical calculations by automating them with digital computers.
Private life members on the voyage to South Africa, 1905. Brown is seated at bottom right. Brown never married, and for most of his adult life lived with his unmarried younger sister, Mildred, who kept house for him. She made it her job to shield him from "cares and disturbances" and succeeded in "utterly spoiling him." His daily routine was unusual, and was described as follows: ''He was in the habit of going to bed early and as a consequence woke up between three and five o'clock in the morning. After having fortified himself with strong coffee from a thermos bottle he set to work without leaving his bed, smoking numerous cigarettes. His serious scientific work was thus done before he got up for breakfast at nine o'clock.''
Death A heavy smoker, Brown suffered from bronchial trouble for much of his life. He was afflicted by ill-health during most of the six years of his retirement, and died in
New Haven, Connecticut in 1938. His sister, Mildred, had died a few years before him and his only surviving close family was his widowed older sister, Ella Yorke, who had emigrated with her husband to
New Zealand in the 1890s. ==Legacy==