Margaret Hamilton, the computing pioneer who led development of Apollo’s onboard flight software at MIT, died September 30 in Cambridge, Massachusetts, aged 90, according to MIT News.

Her lasting contribution was an insistence that software must handle the unexpected.

During Apollo 11’s descent in July 1969, computer overload alarms threatened to interrupt the landing.

The team’s software preserved essential operations while setting less urgent tasks aside, allowing the astronauts to proceed with Mission Control’s approval.

Wikipedia Commons / NASA
Beyond Apollo, Hamilton helped establish software engineering as a serious discipline.

A photograph of her beside towering stacks of printed code later introduced her achievements to new generations, and President Barack Obama awarded her the Presidential Medal of Freedom in 2016. She also balanced demanding work with raising her daughter, Lauren.

Her legacy belongs alongside the footprints on the moon: proof that extraordinary journeys depend on people who anticipate trouble long before the world sees it.

Hamilton in 1969, standing next to listings of the Apollo guidance software she and her MIT team produced / Wikipedia Commons

President Barack Obama awarded the Presidential Medal of Freedom to Margaret H. Hamilton,

a pioneering computer scientist and former head of the Software Engineering Division of MIT’s

Instrumentation Laboratory who led the development of on-board flight software for NASA’s Apollo moon missions. (Photo by Cheriss May/NurPhoto via Getty Images)