Nearly fifty years ago, Neil Armstrong took his famous first small step on the surface of the moon. Though people all over the US celebrated the monumental historical moment, arguably none were more excited or relieved than Margaret Hamilton, who led the MIT team responsible for the software that made a moon landing possible. Hamilton’s innovation and accomplishments helped pave the way for women in computer science disciplines during a Mad Men like era where women were a huge minority in the field.

In 1960, the 24 year-old Earlham College mathematics graduate took an interim position as software developer at MIT, supporting her husband during his stint at Harvard Law School. But just one year later, MIT’s Instrumentation Laboratory was tasked with developing the software for the Apollo 11 mission.

Throughout the 11 year span of the project, Hamilton rose through the ranks, eventually becoming the director of the Software Engineering Division, where she helped develop the asynchronous software and priority scheduling, innovations which were necessary for Apollo 11’s landing. This software allows a computer to prioritize important tasks, while placing other standard, less necessary functions on hold until the priority tasks are completed.

Three minutes before the Lunar lander reached the Moon’s surface, several computer alarms on board were triggered, indicating that the computer was overloaded with incoming data. In a letter to Datamation in 1971, Hamilton wrote:

Due to an error in the checklist manual, the rendezvous radar switch was placed in the wrong position. This caused it to send erroneous signals to the computer. The result was that the computer was being asked to perform all of its normal functions for landing while receiving an extra load of spurious data which used up 15% of its time. The computer (or rather the software in it) was smart enough to recognize that it was being asked to perform more tasks than it should be performing…The software’s action [eliminated] lower priority tasks and re-established the more important ones … If the computer hadn’t recognized this problem and taken recovery action, I doubt if Apollo 11 would have been the successful moon landing it was.

The work that Hamilton and her team accomplished was instrumental to the creation of the Computer Science field, as they worked to gain hands-on experience during a time when these professions were more like the Wild West than an actual discipline.

Since Hamilton’s contributions to Apollo 11, the Computer Science field has rapidly expanded, necessitating the need to learn code in almost every industry, from healthcare, to fashion, to music.

However, despite the fact a woman was at the heart of the lunar landing in the 1970s, the number of women in STEM fields today is staggeringly low. And although there have been efforts by many programs encouraging girls to learn how to code, the number of women in computer science positions has dropped by nearly 20% since the 1980s.

But there’s still hope for women in the profession. Some colleges have taken a deliberate approach to attract and keep more female students in their classrooms, and the ways in which the STEM fields are inhospitable to women are being highlighted and discussed more and more as the gender disparity increases.

As we look to the future of STEM, it’s important also to look back at the women who helped pave the way for people of all genders. Although Aldrin’s triumph is one to be celebrated as a giant leap for mankind and a step toward the future, his accomplishments would have been impossible had it not been for the women behind the scenes.

Written for Sheroes of History by Danika McClure. Danika is a musician from the northwest who sometimes takes a 30 minute break from writing to enjoy a TV show. Lover of Drake, guacamole, and angry girl music of the indie rock persuasion. You can follow her on twitter @sadwhitegrrl

Find out more…

Danika suggests these articles to find out more about Margaret’s achievements:

Her Code Got Humans on the Moon–and Invented Software Itself

Margaret Hamilton, lead software engineer, Project Apollo

Meet Margaret Hamilton, the badass ‘60s programmer who saved the moon landing

This short animated video is about Margaret’s life:

https://www.youtube.com/watch?v=mE0GVrXjOYQ