George Biddell Airy

b. 27 July 1801, Northumberland Co., England
d. 2 January 1892, Greenwich, London, England

Airy was an English mathematician and astronomer. He enjoyed a brilliant career at Trinity College, Cambridge, which he entered in1819, graduating in 1822. Two years later he was elected a fellow of Trinity. In 1826 he was appointed Lucasian professor Mathematics and very soon after was elected Plumian professor Astronomy and director of the new Cambridge observatory (1828). He was appointed the Astronomer Royal in 1835, holding the position until 1881. Airy’s many achievements include work on planetary orbits, measuring the mean density of the earth, and, in 1851, establishing Greenwich as the location of the prime meridian. This was the 4th Greenwich meridian, and became the definitive internationally recognised line in 1884. Airy was a member of the Royal Society and the Royal Astronomical Society. A Martian crater is named for him, as is a lunar crater. His autobiography, published in 1896, includes a complete list of his 518 published papers. His 1861 paper “On the algebraic and numerical theory of errors of observations and the combination of observations” would have appeared just after the period of time when he was corresponding with Dr. Jack.