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NASA’s first software engineer: Margaret Hamilton - Matt Porter and Margaret Hamilton

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    At roughly 4pm on July 20, 1969,
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    mankind was just minutes away from
    landing on the surface of the moon.
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    But before the astronauts began
    their final descent,
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    an emergency alarm lit up.
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    Something was overloading the
    computer,
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    and threatened to abort the landing.
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    Back on Earth, Margaret Hamilton held
    her breath.
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    She'd led the team developing the
    pioneering in-flight software,
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    so she knew this mission had no
    room for error.
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    But the nature of this last-second
    emergency
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    would soon prove her software
    was working exactly as planned.
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    Born 33 years earlier in Paoli, Indiana,
    Hamilton had always been inquisitive.
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    In college, she studied mathematics
    and philosophy,
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    before taking a research position at the
    Massachusetts Institute of Technology
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    to pay for grad school.
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    Here, she encountered her first computer
    while developing software
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    to support research into the new
    field of chaos theory.
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    Next at MIT's Lincoln Laboratory,
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    Hamilton developed software for
    America’s first air defense system
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    to search for enemy aircraft.
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    But when she heard that renowned
    engineer Charles Draper
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    was looking for help sending mankind
    to the moon,
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    she immediately joined his team.
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    NASA looked to Draper and his group of
    over 400 engineers
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    to invent the first compact digital flight
    computer, the Apollo Guidance Computer.
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    Using input from astronauts, this device
    would be responsible for guiding,
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    navigating and controlling the spacecraft.
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    At a time when unreliable computers
    filled entire rooms,
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    the AGC needed to operate without
    any errors,
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    and fit in one cubic foot of space.
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    Draper divided the lab into two teams,
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    one for designing hardware and one
    for developing software.
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    Hamilton led the team that built the
    on-board flight software
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    for both the Command and Lunar Modules.
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    This work, for which she coined the term
    “software engineering,"
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    was incredibly high stakes.
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    Human lives were on the line,
    so every program had to be perfect.
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    Margaret’s software needed to quickly
    detect unexpected errors
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    and recover from them in real time.
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    But this kind of adaptable program was
    difficult to build,
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    since early software could only process
    jobs in a predetermined order.
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    To solve this problem, Margaret designed
    her program to be “asynchronous,”
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    meaning the software's more important
    jobs would interrupt less important ones.
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    Her team assigned every task a unique
    priority
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    to ensure that each job occurred in the
    correct order and at the right time–
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    regardless of any surprises.
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    After this breakthrough,
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    Margaret realized her software could help
    the astronauts work
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    in an asynchronous environment as well.
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    She designed Priority Displays
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    that would interrupt astronaut’s
    regularly scheduled tasks
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    to warn them of emergencies.
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    The astronaut could then communicate
    with Mission Control
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    to determine the best path forward.
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    This marked the first time flight software
    communicated directly―
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    and asynchronously―with a pilot.
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    It was these fail safes that triggered the
    alarms just before the lunar landing.
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    Buzz Aldrin quickly realized his mistake–
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    he’d inadvertently flipped the
    rendezvous radar switch.
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    This radar would be essential on their
    journey home,
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    but here it was using up vital
    computational resources.
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    Fortunately, the Apollo Guidance Computer
    was well equipped to manage this.
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    During the overload, the software
    restart programs
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    allowed only the highest priority jobs
    to be processed––
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    including the programs
    necessary for landing.
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    The Priority Displays gave the
    astronauts a choice––
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    to land or not to land.
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    With minutes to spare, mission
    control gave the order.
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    The Apollo 11 landing was about the
    astronauts, mission control,
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    software and hardware all working together
    as an integrated system of systems.
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    Hamilton’s contributions were essential
    to the work of engineers and scientists
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    inspired by President John F.
    Kennedy’s goal to reach the Moon.
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    And her life-saving work went far
    beyond Apollo 11––
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    no bugs were ever found in the in-flight
    software for any crewed Apollo missions.
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    After her work on Apollo,
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    Hamilton founded a company that uses
    its unique universal systems language
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    to create breakthroughs for systems
    and software.
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    In 2003, NASA honored her achievements
    with the largest financial award
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    they’d ever given to an individual.
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    And forty-seven years after her software
    first guided astronauts to the moon,
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    Hamilton was awarded the presidential
    Medal of Freedom
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    for changing the way we think
    about technology.
Title:
NASA’s first software engineer: Margaret Hamilton - Matt Porter and Margaret Hamilton
Speaker:
Matt Porter and Margaret Hamilton
Description:

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Video Language:
English
Team:
closed TED
Project:
TED-Ed
Duration:
04:49

English subtitles

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