Monday, July 6, 2020

Gladys West, mathematician and geodesist who found the Earth's shape for GPS

Gladys West, linocut, 11" x 14" by Ele Willoughby, 2020


Geodesy is the study of the shape of the Earth. The Earth isn’t a ball so much as an oblate spheroid- that means it’s a bit of a flattened oval in cross-section. Further there are bumps and divots, deviations from the reference ellipsoid. Measuring these deviations teaches us about our Earth and oceans, and the orbital dynamics of satellites. This mathematician and geodesist only started to get the recognition she deserves in recent years for the role she played in various satellite programs, including most famously the Global Positioning System (GPS).  

Gladys Mae West (née Brown) was born in 1930 in in Sutherland, Dinwiddie County, in rural Virginia. Her family were farmers in a community of share-croppers; her mother also worked at a tobacco company and her father also worked for the railroad. She decided early on that she needed an education if she didn't want to work in a factory or in the cotton, corn or tobacco fields. She secured a scholarship to Virginia State University, a HBPU (Historically Black Public University) as her high school class valedictorian. A great all-around student, she was unsure what subject to pursue but was encouraged to major in science and math since fewer people had the aptitude to tackle them. She choose the male-dominated field of mathematics, and joined the Alpha Kappa Alpha sorority. She graduated with a Bachelor of Science in Mathematics in 1952 and taught math and science for two years before returning to complete her Masters in Mathematics at VSU in 1955. She taught again briefly before starting her career at the Naval Proving Ground in Dahlgren, Virginia (now the Naval Surface Warfare Center) in the US in 1956. There were only 3 other Black people there, one woman and two men, and she says felt the pressure to always do everything right and set an example. She was hired as a computer programmer in the Naval Surface Warfare Center Dahlgren Division and a project manager for satellite data-processing systems. All the while, she earned a second Master's in public administration from the University of Oklahoma.

She fell in love with one of her two male, Black mathematician colleagues, Ira West. They married, had three children (and now seven grandchildren) and have been together for over 60 years.

In the 1960s, she participated in an award winning study which  proved the regularity of Pluto’s motion relative to Neptune. She then began using satellite altimeter data to model the Earth's shape, particularly the oceans. Her hard work paid off, when her department head recommended her for a commendation 1979 and she became the project manager for the Seasat radar altimetry project, the first remote sensing satellite for the oceans. From the mid 70s through the 80s West developed complex algorithms for an IBM 7030 “Stretch” computer in order to model distortions in the Earth's shape due to gravitational, tidal and other forces. Her calculations produced an extremely accurate geodetic Earth model, or geoid, optimized to determine the sallite orbits of what we now know as the Global Positioning System. She thus played a pivotal role in the development of technology which is so central to our lives, as GPS is embedded in industry, navigation, telecommunications and applications which exceed anything the US Navy could ever have imagined.

In 1986, West also published Data Processing System Specifications for the Geosat Satellite Radar Altimeter, a 51-page technical report for the Naval Surface Weapons Center (NSWC), a guide to increase the accuracy of the estimation of geoid heights and vertical deflection, based on Geosat radio altimetry data.

My portrait features three of the satellites central to her carreer: Seasat, a GPS satellite and GEOS-3, as well as the satellite paths for Geosat based on her own publications.

After 42 years, she retired 1998. She and Ira travelled, but she decided to return to academia and pursue a doctorate. She suffered a stroke which impacted her hearing, vision, balance and mobility, but despite this, she persisted and completed a PhD in Public Administration from Virginia Tech in 2018 at age 88!

Her acheivements only started to receive recognition when a sorority sister from Alpha Kappa Alpha read the brief bio she submitted for an alumni function and pointed out to her that she was a "Hidden Figure" of GPS. Her story started to be covered in the press. She was officially recognised by the Virginia Senate and she was inducted into the United States Air Force Hall of Fame in 2018, one of the highest honors bestowed by Air Force Space Command (AFSPC).

References

Amelia Butterly, '100 Women: Gladys West - the 'hidden figure' of GPS,' BBC.com, May 20, 2018

Air Force Space Command Public Affairs, 'Mathematician inducted into Space and Missiles Pioneers Hall of Fame,' December 07, 2018
 
Cathy Dyson, 'Gladys West's work on GPS 'would impact the world,' January 19, 2018,
The Free Lance Star, Fredericksburg.com

Gladys West, wikipedia, accessed July 6, 2020 

West, Gladys B. (June 1986). "Data Processing System Specifications for the Geosat Satellite Radar Altimeter" (PDF). Naval Surface Weapons Center, Report NSWC TR 86-149.

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