Margaret Hamilton, whose code guided Apollo 11 to the lunar surface, dies

The computer scientist behind groundbreaking research that helped land Nasa's astronauts on the Moon has died aged 90. Margaret Hamilton was a trailblazer in her field, leading the team that developed the software for Nasa's Apollo missions and coining the term "software engineering". Her former employer, the Massachusetts Institute of Technology, confirmed her death on 30 September.

"To say Hamilton was a pioneer — to say she was ahead of her time — would be a dramatic understatement," MIT said in a statement, acknowledging that she was a software engineer before the discipline became mainstream. Hamilton worked at MIT from 1959 until the mid-1970s and managed its Software Engineering Division. There she led a team of engineers who wrote and tested all onboard in-flight software for Nasa's Apollo 11 project, the code that guided Neil Armstrong and Buzz Aldrin to land safely on the Moon.

"I was attracted both by the sheer idea and the fact that it had never been done before," she told the Guardian in 2019. "I was the first programmer to join and the first woman they hired." In 1969, moments before the historic landing, an onboard computer raised an alarm signalling an error. The error detected that the computer was overloaded, and for a moment it looked as though the complex landing might not be achieved. But Hamilton and her team had planned for such a failure, engineering "priority-driven software" that shut down background tasks and favoured the most important one: the Moon landing. Their work was immortalised in a 1969 photograph of Hamilton standing beside a stack of printed code that towered to her own height.

In 2016, Barack Obama honoured her life's work with the Presidential Medal of Freedom for her contribution to science and space travel. At the time, Obama said Hamilton "symbolises that generation of unsung women who helped send humankind into space". Born in Indiana in 1936, she first studied mathematics at the University of Michigan in 1955 before moving to Earlham College, where she took a BA in mathematics in 1958. A year later she moved to Boston with her husband and originally took the job at MIT to support him through his law degree.

From the 1970s onwards, Hamilton used her expertise to found her own software businesses, including Hamilton Technologies, which remains based in Massachusetts. "We are saddened by her death, but grateful for the opportunity to have celebrated her extraordinary achievements throughout her long life," Earlham College said in a statement. "Her pioneering spirit and remarkable legacy will continue to inspire generations of Earlhamites." Hamilton is survived by her daughter, a son-in-law, two grandsons and four great-grandchildren, according to MIT.