Person: Clark (2), John Brown
Ernest Brown worked on lunar and planetary motion.
Mathematical Profile (Excerpt):
 Brown received his B.A. in 1887 when he was ranked Sixth Wrangler in the Mathematical Tripos (meaning he was the sixth best student with First Class honours in mathematics).
 Brown was appointed as an instructor in mathematics at Haverford College, Pennsylvania in 1891 then, in 1893, he was promoted to full Professor of Applied Mathematics.
 While he had worked in Cambridge, before going to the United States, Brown had read Hill's Researches in the lunar theory (1878) and published his own ideas on that theory.
 Newcomb was constructing tables of planetary motion when Brown arrived in the United States and Newcomb had persuaded Hill to help him out by working on the motion of Jupiter and Saturn.
 As this meant that Hill was no longer working on the motion of the Moon, Brown thought that the field was open and so began work himself in that area.
 After 30 years of work, Brown published his lunar tables Tables of the Motion of the Moon in 1919.
 In 1926 Brown published a paper in which he ascribed these fluctuation to irregular changes in the Earth's period of rotation which has subsequently proved correct.
 Not only did Brown contribute greatly to the theory of the Moon's orbit but he also worked on planetary motion.
 Brown received many awards for his work.
Born 29 November 1866, Hull, Yorkshire, England. Died 23 July 1938, New Haven, Connecticut, USA.
View full biography at MacTutor
Tags relevant for this person:
Astronomy, Origin England, Physics
Thank you to the contributors under CC BYSA 4.0!
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 @JJO'Connor
 @EFRobertson
References
Adapted from other CC BYSA 4.0 Sources:
 Oâ€™Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive