12/10/2025
I think that is one of the components of "sustainability"--recognizing the contributions that each of us might make--to build community, to respect everyone, and to make advances that take us further than before.
When NASA told her software wasn't "real engineering," she invented the term "software engineering" to prove them wrong—then her code saved Apollo 11 from disaster.
In 1960, Margaret Hamilton needed a job. Her husband was in law school at Harvard. They had a young daughter. Money was tight. Someone mentioned MIT's Instrumentation Laboratory was hiring programmers.
Margaret had a mathematics degree but no programming experience. She applied anyway, thinking it would be temporary work—just until her husband graduated and could support the family.
She had no idea she was about to invent a profession that would change human civilization.
When Margaret started at MIT, "programmer" meant something closer to secretary than engineer. You took specifications that real engineers—the hardware people, the rocket scientists—gave you, and you translated them into computer instructions. It was considered detail work. Administrative. Something women could do precisely because it wasn't seen as important.
Margaret looked at this arrangement and thought: this is completely backwards.
The computer isn't just following instructions. The computer is making thousands of critical decisions every second. If the software fails, nothing else matters. The hardware is useless. The brilliant rocket design is irrelevant. Everyone dies.
Software isn't secondary to the mission. Software IS the mission.
But when Margaret tried explaining this to NASA engineers, many dismissed her concerns. Hardware was real engineering—metal and electronics you could touch, test, see. Software was just... instructions. Typing. Women's work.
Margaret was so frustrated by this attitude that she started using a new term for what she was doing. She called it "software engineering" and insisted it be treated with the same rigor, respect, and resources as any other engineering discipline.
People thought she was being pretentious. Engineering was building bridges and rockets. Writing code wasn't engineering.
Margaret ignored them and started building Apollo's software as if lives depended on it.
Because lives did depend on it.
NASA was asking her team to do something that had never been done: write software for a computer that would operate completely autonomously in space, managing life support, navigation, and thrust control with no possibility of real-time intervention from Earth.
The Apollo Guidance Computer had roughly 72 kilobytes of memory—less storage than the smallest modern email attachment. They were working with punch cards and mainframe computers, debugging by hand, unable to make mistakes because there would be no patches, no updates, no second chances.
And Margaret's team had to anticipate every possible failure mode.
What if astronauts accidentally pressed the wrong buttons? What if sensors failed? What if the computer received contradictory data? What if multiple systems demanded processing power simultaneously?
Margaret's approach was revolutionary: build intelligence into the system itself. Make the computer capable of recognizing problems and solving them autonomously.
She designed priority systems—hierarchies of what mattered most. If the computer got overwhelmed, it could shed lower-priority tasks to focus on keeping astronauts alive.
She built error detection throughout the code—constant self-checking to catch problems before they became catastrophic.
She created restart capabilities—if something crashed, the system could recover automatically rather than failing completely.
Some NASA managers thought this was overkill. The missions would be carefully planned. Astronauts would be perfectly trained. Why build in so much redundancy? Why waste precious memory on unlikely scenarios?
Margaret insisted. She fought for every line of error-handling code. She ran endless simulations. She prepared for disasters that hadn't happened yet.
And then came July 20, 1969.
Neil Armstrong and Buzz Aldrin were descending toward the moon in the lunar module Eagle. The whole world was watching—600 million people glued to television sets, witnessing humanity's greatest adventure.
Three minutes before touchdown, warning alarms erupted in the spacecraft.
The computer was overloaded, drowning in data, struggling to process everything simultaneously. At Mission Control in Houston, controllers stared at their screens in shock. This alarm had barely appeared during years of simulation. No one was entirely sure what it meant.
Should they abort? Bring the astronauts back up and abandon the landing after coming so close?
The flight director needed an answer immediately.
What had happened was mundane but potentially catastrophic: someone had left the rendezvous radar on. It wasn't needed during landing—it would only be necessary later for docking maneuvers. But it was actively flooding the computer with data, competing for processing power while the system was also navigating descent, monitoring fuel levels, controlling thrusters, and managing dozens of other critical functions.
The Apollo Guidance Computer, with its 72 kilobytes of memory, couldn't handle everything at once.
But here's what saved the mission: Margaret Hamilton had anticipated exactly this scenario years earlier.
Her priority systems kicked in automatically. The computer recognized it was overloaded, identified which tasks were essential for survival, and started shedding non-critical functions. The unnecessary rendezvous radar data was deprioritized. Life support continued. Navigation continued. Thrust control continued.
The computer was making autonomous decisions about what mattered most.
A young guidance officer at Mission Control named Jack Garman had memorized alarm codes during training simulations. He recognized 1202 didn't mean system failure—it meant the computer was doing exactly what Hamilton had designed it to do.
"We're go on that alarm," he told the flight director.
The alarms kept blaring—six times during those final minutes. Each time, Hamilton's code was adapting, prioritizing, surviving.
And at 4:17 PM, Armstrong's voice crackled from the moon: "The Eagle has landed."
Back at MIT, Margaret Hamilton wasn't watching from Mission Control with the famous rocket engineers. She wasn't on television. She was back at her lab, monitoring from a distance, trusting that years of work had been enough.
It had been enough. Her code had saved the most famous mission in human history.
But the recognition didn't come. Armstrong and Aldrin became household names instantly. Mission Control became legendary. Even the flight director who'd made the final call got recognition.
But the woman whose code had actually made the life-or-death decisions? Most people never heard her name.
For decades, Margaret Hamilton continued working in software development, consulting, founding companies. She became successful within aerospace circles. But public recognition for Apollo? Almost none.
In 2003, NASA finally gave her a special award. In 2016, President Obama awarded her the Presidential Medal of Freedom.
She was eighty years old by then—47 years after Apollo 11.
But Margaret's real legacy isn't awards. It's the world we live in.
That term she invented—"software engineering"—is now one of the highest-paid, most respected professions globally. Universities offer degrees in it. Companies compete for software engineers.
Every priority system in modern computing—every phone managing multiple apps, every computer juggling tasks, every system that can recover from errors—traces back to principles Margaret established for Apollo.
She proved software wasn't clerical work but the foundation everything else rests on.
She built resilience into systems that now run hospitals, power grids, financial markets, transportation networks.
She demonstrated that anticipating failure is more important than celebrating success.
Margaret Hamilton was told programming wasn't real engineering.
So she invented software engineering, built systems that saved lives 240,000 miles from Earth, and created the foundation for modern civilization.
All while being dismissed as doing "women's work."
She didn't go to the moon.
But she made damn sure everyone else could.
