Margaret Hamilton

Margaret Elaine Hamilton (née Heafield; born August 17, 1936) is an American computer scientist. She directed the Software Engineering Division at the MIT Instrumentation Laboratory, where she led the development of the on-board flight software for NASA's Apollo Guidance Computer for the Apollo program. She later founded two software companies, Higher Order Software in 1976 and Hamilton Technologies in 1986, both in Cambridge, Massachusetts.

Hamilton has published more than 130 papers, proceedings, and reports, about sixty projects, and six major programs. She coined the term "software engineering", stating, "I began to use the term 'software engineering' to distinguish it from hardware and other kinds of engineering, yet treat each type of engineering as part of the overall systems engineering process."

On November 22, 2016, Hamilton received the Presidential Medal of Freedom from President Barack Obama for her work leading to the development of on-board flight software for NASA's Apollo Moon missions.

Margaret Elaine Heafield was born August 17, 1936, in Paoli, Indiana, to Kenneth Heafield and Ruth Esther Heafield (née Partington). The family later moved to Michigan, where Margaret graduated from Hancock High School in 1954.

She studied mathematics at the University of Michigan in 1955 before transferring to Earlham College, where her mother had been a student. She earned a BA in mathematics with a minor in philosophy in 1958. She cites Florence Long, the head of the math department at Earlham, as helping with her desire to pursue abstract mathematics and become a mathematics professor.

She says her poet father and headmaster grandfather inspired her to include a minor in philosophy in her studies.

In Boston, Hamilton initially intended to enroll in graduate study in abstract mathematics at Brandeis University. However, in mid-1959, Hamilton began working for Edward Norton Lorenz, in the meteorology department at Massachusetts Institute of Technology (MIT). She developed software for predicting weather, programming on the LGP-30 and the PDP-1 computers at Marvin Minsky's Project MAC. Her work contributed to Lorenz's future publications on chaos theory, as acknowledged by Lorenz himself. At the time, computer science and software engineering were not yet established disciplines; instead, programmers learned on the job with hands-on experience. She moved on to another project in the summer of 1961, and hired and trained Ellen Fetter as her replacement.

From 1961 to 1963, Hamilton worked on the Semi-Automatic Ground Environment (SAGE) Project at the MIT Lincoln Lab, where she was one of the programmers who wrote software for the prototype AN/FSQ-7 computer (the XD-1), used by the U.S. Air Force to search for possibly unfriendly aircraft. She also wrote software for a satellite tracking project at the Air Force Cambridge Research Laboratories. The SAGE Project was an extension of Project Whirlwind, started by MIT to create a computer system that could predict weather systems and track their movements using simulators. SAGE was soon developed for military use in anti-aircraft air defense. Hamilton said:

What they used to do when you came into this organization as a beginner, was to assign you this program which nobody was able to ever figure out or get to run. When I was the beginner they gave it to me as well. And what had happened was it was tricky programming, and the person who wrote it took delight in the fact that all of his comments were in Greek and Latin. So I was assigned this program and I actually got it to work. It even printed out its answers in Latin and Greek. I was the first one to get it to work.

It was her efforts on this project that made her a candidate for the position at NASA as the lead developer for Apollo flight software.

Hamilton learned of the Apollo project in 1965 and wanted to get involved due to it being "very exciting" as a Moon program. She joined the MIT Instrumentation Laboratory, which developed the Apollo Guidance Computer for the Apollo lunar exploration program. Hamilton was not the first programmer hired for the Apollo project at MIT (despite ), because she joined several years after the project started in 1961. Hamilton was the first female programmer in the project, and later became Director of the Software Engineering Division. She was responsible for the team writing and testing all onboard in-flight software for the Apollo spacecraft's Command and Lunar Module and for the subsequent Skylab space station. Another part of her team designed and developed the systems software. This included error detection and recovery software such as restarts and the Display Interface Routines (also known as the Priority Displays), which Hamilton designed and developed. She worked to gain hands-on experience during a time when computer science courses were uncommon and software engineering courses did not exist.

Hamilton has been credited with naming the discipline of "software engineering". Hamilton details how she came to make up the term "software engineering":

When I first came up with the term, no one had heard of it before, at least in our world. It was an ongoing joke for a long time. They liked to kid me about my radical ideas. It was a memorable day when one of the most respected hardware gurus explained to everyone in a meeting that he agreed with me that the process of building software should also be considered an engineering discipline, just like with hardware. Not because of his acceptance of the new 'term' per se, but because we had earned his and the acceptance of the others in the room as being in an engineering field in its own right.

When Hamilton started using the term "software engineering" during the early Apollo missions, software development was not taken seriously compared to other engineering disciplines, nor was it regarded as a science. Hamilton was concerned with legitimizing software development as an engineering discipline. Over time the term "software engineering" gained the same respect as any other technical discipline. The IEEE Software September/October 2018 issue celebrates the 50th anniversary of software engineering. Hamilton talks about "Errors" and how they influenced her work related to software engineering and how her language, USL, could be used to prevent the majority of "Errors" in a system. With USL, rather than continuing to test for errors, her program was designed to keep most errors out of the system from the beginning. USL was created after her knowledge and experience from the Apollo mission, in which she determined a mathematical theory for systems and software. This method was then, and still is, highly impactful to the field of software engineering. Writing in Wired, Robert McMillan noted: "At MIT she assisted in the creation of the core principles in computer programming as she worked with her colleagues in writing code for the world's first portable computer". Hamilton's innovations go beyond playing an important role in getting humans to the Moon. According to Wired's Karen Tegan Padir: "She, along with that other early programming pioneer, COBOL inventor [sic] Grace Hopper, also deserve tremendous credit for helping to open the door for more women to enter and succeed in STEM fields like software."

In 2017, a "Women of NASA" LEGO set went on sale featuring minifigures of Hamilton, astronauts Mae Jemison and Sally Ride, and NASA's first Chief of Astronomy, Nancy Grace Roman. The set was initially proposed by Maia Weinstock as a tribute to the women's contributions to NASA history, and Hamilton's section of the set features a recreation of her famous 1969 photo posing with a stack of her software listings.

In 2019, to celebrate 50 years after the Apollo landing, Google decided to make a tribute to Hamilton. The mirrors at the Ivanpah Solar Power Facility were configured to create a picture of Hamilton and the Apollo 11 by moonlight.

In 1986, Hamilton received the Augusta Ada Lovelace Award by the Association for Women in Computing.

In 2003, she was given the NASA Exceptional Space Act Award for scientific and technical contributions. The award included $37,200, the largest amount awarded to any individual in NASA's history.

In 2009, she received the Outstanding Alumni Award from Earlham College.

In 2016, she received the Presidential Medal of Freedom from Barack Obama, the highest civilian honor in the United States.

On April 28, 2017, she received the Computer History Museum Fellow Award, which honors exceptional men and women whose computing ideas have changed the world.

Hamilton, M.; Zeldin, S. (March 1976). "Higher Order Software—A Methodology for Defining Software". IEEE Transactions on Software Engineering. SE-2 (1): 9–32. doi:10.1109/TSE.1976.233798. S2CID 7799553.

Hamilton, M.; Zeldin, S. (January 1, 1979). "The relationship between design and verification". Journal of Systems and Software. 1: 29–56. doi:10.1016/0164-1212(79)90004-9.

Hamilton, M. (April 1994). "Inside Development Before the Fact". (Cover story). Special Editorial Supplement. 8ES-24ES. Electronic Design.

Hamilton, M. (June 1994). "001: A Full Life Cycle Systems Engineering and Software Development Environment". (Cover story). Special Editorial Supplement. 22ES-30ES. Electronic Design.

Hamilton, M.; Hackler, W. R. (2004). "Deeply Integrated Guidance Navigation Unit (DI-GNU) Common Software Architecture Principles". (Revised December 29, 2004). DAAAE30-02-D-1020 and DAAB07-98-D-H502/0180, Picatinny Arsenal, NJ, 2003–2004.

She met her first husband, James Cox Hamilton, in the mid-1950s while attending college. They were married on June 15, 1958, the summer after she graduated from Earlham. She briefly taught high school mathematics and French at a public school in Boston, Indiana. The couple then moved to Boston, Massachusetts, where they had a daughter, Lauren, born on November 10, 1959. They divorced in 1967 and Margaret married Dan Lickly two years later.