Margaret Hamilton, a 32-year-old mother and computer whiz at the Massachusetts Institute of Technology, wrote the software that placed Neil Armstrong and Buzz Aldrin on the moon on 20 July 1969. She also worked on the five moon-landing missions that followed.
The director of software engineering at MIT's Instrumentation Laboratory, Hamilton was a pioneer of computer science in a transformative era, and on a transformative mission, in human history.
Working in fields dominated by men, Hamilton - who was born in Indiana in 1936 - often had her toddler at her side as she wrote the code that changed mankind’s relationship with the heavens forever. She is also credited with coining the phrase "software engineer" - a job title now ubiquitous in business culture.
Yet Hamilton lived in the shadows of NASA lore for decades - her name and incredible role in one of humanity's greatest achievements known only to friends and Apollo program insiders.
"I was surprised to discover she was never formally recognized for her groundbreaking work," Dr. Paul Curto, senior technologist for NASA's Inventions and Contributions Board, said in 2003 when Hamilton was finally honored with a NASA Exceptional Space Act Award.
"Her concepts of asynchronous software, priority scheduling, end-to-end testing and man-in-the-loop decision capability, such as priority displays, became the foundation for ultra-reliable software design."