Elizabeth Langdon Williams (February 8, 1879 – 1981) was an American
human computer
The term "computer", in use from the early 17th century (the first known written reference dates from 1613), meant "one who computes": a person performing mathematical calculations, before electronic calculators became available. Alan Turing ...
and
astronomer
An astronomer is a scientist in the field of astronomy who focuses on a specific question or field outside the scope of Earth. Astronomers observe astronomical objects, such as stars, planets, natural satellite, moons, comets and galaxy, galax ...
whose work helped lead to the discovery of Pluto, or Planet X.
Personal life and education
Elizabeth Langdon Williams was born to Elizabeth Brigham and Louis M. Williams on February 8, 1879 in
Putnam, Connecticut. She was the twin of Robert Longfellow Williams, and the older sister of Henry Trumbell Williams and Ursula Louise Williams.
She graduated from
MIT
The Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of modern technology and sc ...
with a degree in physics in 1903 as one of their earliest female graduates, and was the first woman to play an honor part during graduation. She read part of her thesis, "An analytical study of the Fresnel wave-surface" at the ceremony, and was said to have widely impressed all in attendance. She was at the top of her class and said to be ambidextrous, writing cursive with her right hand and print with her left hand.
In 1922, Williams married George Hall Hamilton, another astronomer who was born in
London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...
on June 30, 1884 and educated at
Cambridge
Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 Unit ...
. He worked at the
Lowell Observatory
Lowell Observatory is an astronomical observatory in Flagstaff, Arizona, United States. Lowell Observatory was established in 1894, placing it among the oldest observatories in the United States, and was designated a National Historic Landmark ...
in
Flagstaff, Arizona
Flagstaff ( ), known locally as Flag, is the county seat of Coconino County, Arizona, in the southwestern United States. As of the 2020 United States census, the city's population was 76,831.
Flagstaff is the principal city of the Coconino Cou ...
, where he met Williams, from 1917 to 1922.
Career
Williams was hired by
Percival Lowell in 1905 to work from his State Street office in
Boston
Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeas ...
.
She initially edited publications for Lowell
until she was asked to be a human computer for his Planet X research that began in 1910.
Planet X
Lowell hypothesized that a proposed Planet X affected the orbits of the known planets Neptune
Neptune is the eighth and farthest known planet from the Sun. It is the List of Solar System objects by size, fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 t ...
and Uranus
Uranus is the seventh planet from the Sun. It is a gaseous cyan-coloured ice giant. Most of the planet is made of water, ammonia, and methane in a Supercritical fluid, supercritical phase of matter, which astronomy calls "ice" or Volatile ( ...
. Williams' role in the Planet X project was that of head human computer, performing mathematical calculations on where Lowell should search for an unknown object and its size based on the differences in the orbits of Neptune and Uranus. Her calculations led to predictions for the location of the unknown planet, but Lowell died in 1916 and the project was discontinued. In the late 1920s, however, the project was resumed and Clyde Tombaugh was hired to lead it. Tombaugh used Lowell's predictions (built on Williams' calculations) to locate an image in a region of the sky photographed in 1915 that he identified as a new planet named Pluto
Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of Trans-Neptunian object, bodies beyond the orbit of Neptune. It is the ninth-largest and tenth-most-massive known object to directly orbit the Su ...
in 1930.
Williams continued to work on calculations and handled correspondence at Lowell Observatory after Lowell's death, moving from Boston to the observatory itself at Flagstaff in 1919. She and Hamilton were then dismissed from their positions at the observatory by Percival Lowell's widow, Constance, because it was considered inappropriate to employ a married woman.
Williams and her husband were subsequently employed at an observatory in
Mandeville, Jamaica
Mandeville () is the capital and largest town in the Manchester Parish, parish of Manchester in the county of Middlesex, Jamaica. In 2005, the town had an estimated population of 50,000, and including the immediate suburbs within a radius of t ...
run by
Harvard College Observatory
The Harvard College Observatory (HCO) is an institution managing a complex of buildings and multiple instruments used for astronomical research by the Harvard University Department of Astronomy. It is located in Cambridge, Massachusetts, United St ...
where they worked together.
Final years
In 1935, George Hall Hamilton died. Widowed, Williams retired from the observatory in Mandeville and moved to
Lebanon, New Hampshire
Lebanon ( ) is the only city in Grafton County, New Hampshire, United States. The population was 14,282 at the 2020 United States census, 2020 census, up from 13,151 at the 2010 United States census, 2010 census. Lebanon is in western New Hampshi ...
with her younger sister, Louise Ring, where they ran "Peaceful Acres," a summer retreat home. She died in 1981 in Enfield, New Hampshire at the age of 101.
References
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{{DEFAULTSORT:Williams, Elizabeth Langdon
1879 births
1981 deaths
American women astronomers
Human computers
American women centenarians
Massachusetts Institute of Technology alumni