Margaret Hamilton, Software Engineering Pioneer Behind Apollo 11 Flight Code, Dies at 90

Margaret Hamilton, who led the development of onboard flight software for NASA's Apollo program in the 1960s, died last week at the age of 90. She is credited with coining the term “software engineering.” She received the Presidential Medal of Freedom in 2016 and was turned into a LEGO minifigure the following year as part of the “Women of NASA” set.

Path to programming

Hamilton was born in 1936 in Paoli, Indiana, and graduated from Earlham College in 1958 with a mathematics degree. She went on to work for MIT mathematician Edward Lorenz, who was building a mathematical model of the weather. Hamilton programmed his LGP-30 computer, even though neither of them had programming experience and both taught themselves. In 1961 she moved to the SAGE project, writing software for the US Air Force.

The Apollo program

In 1965 she joined MIT's Instrumentation Lab, which was developing software for the Apollo onboard guidance computer. She was the first programmer hired and the first woman on the team, and she worked on six lunar landing missions between 1969 and 1972. By 1968 she was assistant director in charge of the Command and Service Module team.

Hamilton introduced a failsafe that allowed the computer, when overloaded with tasks, to drop less important ones and keep the essential ones. That is what happened during Apollo 11 in 1969: as the Eagle lunar module approached the Moon, the computer began flashing alarms. Thanks to the safeguard, the landing in the Sea of Tranquility went ahead safely.

Later career

After the Apollo program ended, the Instrumentation Lab became the independent Draper Laboratory. In 1976 Hamilton founded Higher Order Software, and in 1985 she founded Hamilton Technologies, whose main product is the Universal Systems Language. The Apollo software was published on GitHub in 2015. Hamilton is survived by her daughter Lauren, a son-in-law, two grandsons, four great-grandchildren, and her siblings.