The problem
Liquid hydrogen is the most energetic practical rocket propellant and the hardest to handle. Centaur's performance had to be modelled before it could be trusted with irreplaceable payloads.
The innovation
Easley developed and analysed code supporting Centaur's design and performance analysis, and later applied the same computational approach to energy-conversion and battery-storage studies.
How it worked
Human computation gave way to programs in the languages of the period; the analysis fed directly into vehicle and system design decisions.
Why it mattered
Centaur became the upper stage that launched planetary probes, weather and communications satellites over decades of missions.
The legacy
Her energy-systems work fed into later research on solar, wind and battery technology.
Sources
Annie Easley oral history and Lewis Research Center technical records
Primary record
Follow the invention
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