The Overbar That Cost a Rocket Its Launch
In July nineteen sixty-two, NASA's Mariner 1 probe veered off course seconds after liftoff and had to be destroyed. While popular legend blames a missing comma or hyphen, the true culprit was a single missing overbar in a handwritten guidance equation. This is the story of how a tiny transcription error in the early days of aerospace programming led to a multi-million dollar catastrophe.
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A missing overbar symbol in the guidance software caused the Mariner One rocket to self-destruct.
The software error triggered aggressive steering commands to correct for non-existent flight deviations.
A hardware failure in the tracking beacon forced the rocket to rely on flawed backup code.
The range safety officer destroyed the vehicle over the Atlantic Ocean two hundred ninety-three seconds after liftoff.
This nineteen sixty-two failure led NASA to establish rigorous independent verification and validation for software.
Early programming required manual translation from handwritten equations to punch cards, increasing the risk of clerical errors.
- 01Intro1 min
- 02Five Minutes to Failure2 min
- 03The Anatomy of a Typo2 min
- 04The Human-Machine Gap3 min
- 05Outro1 min
- July 22, 1962: Mariner 1 Done In by a Typo
- In 1962, a Mariner 1 probe bound for Venus was destroyed 293 ...
- Mariner 1
- In 1962, a single missing character in NASA's guidance ...
- Mariner 1
- Mariner 1
- Watch your word, baby
- The Most Expensive Grammar Mistakes in History
- Mariner 1 destroyed due to code error, July 22, 1962
- Mariner 1 - CenterConsulting
- 16_360_w-18.indd
- Mariner 1 Destroyed - Time and Navigation
- Practicing Safe Software - Smithsonian Magazine
- Static Analysis and Verification of Aerospace ...
- General
- for Space Shuttle Flight Software
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