Space & Aerospace
Geodetic Earth modelling for satellite positioning
The problem
Satellite positioning requires an extremely precise mathematical model of the Earth's irregular shape and gravity field.
The innovation
Programming and refinement of geodetic computations from satellite altimetry data to model the geoid.
How it worked
Vast quantities of satellite observations are reduced by computer into a mathematical surface approximating mean sea level worldwide.
Why it mattered
Improved the accuracy of the reference models underlying GPS.
The legacy
Every satnav fix depends on a geoid model. Precision: this is essential contributing work, not sole invention of GPS.
You use this today
The blue dot on your map.
Sources
NSWC Dahlgren geodesy programme records
Primary record
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