Chapter 5. Loops and Modes
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On January 4, 2004, a 400-pound, six-wheeled, solar-powered robot landed on Mars, in the massive impact crater Gusev. The robot was the $400-million-dollar Spirit rover that had taken over a year to build. As Passport to Knowledge reported, Spirit had just survived the six-month journey to the Red Planet and a perilous landing, including bouncing as high as a four-story building on first impact with the surface. The Jet Propulsion Laboratory (JPL) team that built and commanded the rover thought the worst was behind them. They were wrong.
Once the (literal) dust—red—had settled, Spirit began its mission of taking pictures and performing scientific experiments, rolling toward a nearby destination (“Sleepy Hollow”). But then on January 21, less than three weeks into the mission, something happened. NASA’s Deep Space Network lost contact with Spirit.
At first, the rover’s disappearance was blamed on a thunderstorm in Australia disrupting the network, but no, there was something wrong with Spirit itself. The next day, a transmission arrived from Spirit: a single beep that indicated the rover was still there, but that was all. This was seriously bad. If the problem was a critical hardware failure, the robot was dead and its mission was effectively over.
Trying a number of methods, JPL finally coaxed the rover to send diagnostic data, which it did on January 23. Much ...
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