How "One Small Step For Man" Was Made Possible By One Working Woman

Fifty years ago next weekend, mankind did what seemed as impossible now as it did then—they sent a astronauts to the Moon. Ok, so maybe it doesn't seem that impossible (considering that we are now trying to send astronauts to Mars), but considering the technology available at the time it's no wonder there are so many skeptics. In 1969, there were no smartphones, no cell phones, no Wikidepia or Google to look something up real quick. All of this poses an obvious problem if you're planning to do something no one has ever done before, and you might therefore encounter unknown problems.

Mission Control's computer controlled much of the trip from Earth, which is a good thing considering it was the size of a small room. But the final descent was made by a "micro" computer onboard the space craft, and was a mere 70 lbs. This computer was the smallest and most sofisticated computer in existence at the time. Being advanced, of course, does not prevent a computer from crashing, which is exactly what happened as Buzz Aldrin and Neil Armstrong were mid-way to landing their pod on the Moon.

Imagine you’re in a self driving car, traveling 70 miles an hour toward a solid cement wall. Now imagine that your navigation computer crashes and reboots 5 times in 4 minutes as you hurtle toward the wall at full speed. This was, in effect, what happened to Buzz Aldrin and Neil Armstrong as their 70 pound “mini” computer which controlled their lunar landing crashed repeatedly during their 4 minute decent. 

The onboard computer looks more like a simple calculator than anything we’d recognize as a computer today; made of a numerical keypad and a few additional buttons, the display provided the astronauts information in three lines of coded numbers, which Armstrong had to decode from memory before punching in his numeric responses. Unfortunately, “1202” was not a code he recognized, so every time it displayed on the screen he had to call Houston to ask what he should do. He would wait while the NASA scientists conferred with each other, then they would come back on the line and give him their decision. The answer was always the same—keep going. 

A replica of the onboard computer's display and keypad

It turns out that 1202 was the code the computer displayed when it crashed. Luckily for Aldrin and Armstrong, the computer scientists who designed the computer had made provisions for the computer to save the most important data before crashing, such as their trajectory and location in space. This allowed the decent to be successful, even if it meant the men landed several miles from the intended final location. The number 1202 meant thiis process was working.

The error processing code was created by Margaret Hamilton, a computer scientist at MIT. Her team was in charge of creating the software which landed Apollo 11 on the moon—the coding for this software, when printed, stood as tall as she did. But it was worth every page. Without it, Apollo 11 likely would have crashed as the computer would have been unable to pick up where it had last left off. 

Hamilton with her code

But why did Hamilton do this? In part, because she was a working mother. She had brought her 4 year old daughter Lauren to work with her one day, and the child had been playing in the lunar lander simulator MIT had. Lauren, being 4 years old, did not know the protocols for the astronauts, and pressed a button mid-simulation that crashed the entire computer, losing all of the simulated flight’s navigation data. Hamilton saw this as a potential flaw, and notified her superiors that a backup system should be programmed into the computer to prevent errors from erasing the data from the lander’s navigation system. 

Naturally, her superiors declined, saying an actual astronaut would not make this catastrophic mistake. Several weeks later, when an astronaut pushed the exact same button mid-simulation to the same disasterous results, Hamilton received a call letting her know her team would need to create a work around after all. 

Hamilton with her daughter

Hamilton's team made the necessary updates to the software, and the rest is history.

This is just one example of why having women in the workforce is important. Different people bring different viewpoints when approaching problem-solving. Without this working mom, this story may have ended very differently, and if Apollo 11 had crashed, it could have set back computers and software by decades, and our laptops and smartphones might still be distant dreams.