Margaret Hamilton, the computer scientist who led the team that wrote the on-board flight software for NASA's Apollo missions, has died at the age of 90. MIT announced her death. Other reports say she died on September 30, 2026, in Cambridge, Massachusetts. The cause of death has not been disclosed.

Who Was Margaret Hamilton?

Born Margaret Heafield on August 17, 1936, in Paoli, Indiana, she planned to study abstract mathematics at Brandeis University. She took a job at MIT while her husband attended Harvard Law School, and began by programming software to predict the weather. She also wrote software for an air defense project built to identify enemy aircraft.

Leading Apollo's Flight Software

Hamilton worked first on software for the uncrewed Apollo missions, then was promoted to lead development of the on-board flight software for the crewed flights. She directed the Software Engineering Division at MIT's Instrumentation Laboratory and led a team of about 100 engineers. At the time, no schools taught software engineering, so her team had to solve problems on their own. She is widely credited with popularizing the term "software engineering."

The Apollo 11 Landing

Her work mattered most in the final minutes of the first moon landing. As Apollo 11 neared the surface, the guidance computer signalled an overload. Hamilton's error-detection and recovery design let it prioritize critical tasks and keep going, so the landing was not aborted. Her approach made Apollo's software more robust and resistant to failure.

Later Career and Honors

  • Companies: she founded Higher Order Software in 1976 and Hamilton Technologies in 1986.
  • Research: she published more than 130 papers.
  • NASA honor: she received NASA's Exceptional Space Act Award in 2003.
  • Presidential Medal of Freedom: President Barack Obama presented it to her on November 22, 2016.
  • GitHub: in 2015, the Apollo software she helped develop was posted in full on the code-sharing site.

Tributes

MIT called her influence on computing profound and said she was ahead of her time. Others described her as an inspiration to generations of computer scientists and engineers. Looking back on Apollo, Hamilton once said, "we were the luckiest people in the world."

Survivors and Memorial

Hamilton is survived by her daughter, her son-in-law, two grandsons and four great-grandchildren. A memorial service is planned for spring in Cambridge, Massachusetts.

Key Takeaways

  • Hamilton died at 90, reportedly on September 30, 2026.
  • She led the team that wrote Apollo's on-board flight software.
  • Her error-handling design helped keep the Apollo 11 landing on track.