This is part of IEEE Spectrum's Special Report: Why Mars? Why Now?
The space shuttle Columbia has a problem: During launch, foam from the external tank breaks off, strikes the orbiter’s wing, and damages the heat shield. Because the crew members don’t know how the problem will affect reentry, they evacuate to the International Space Station and place Columbia on autopilot, which guides the shuttle to a near-perfect landing. NASA engineers then spend months testing the shuttle during fully automated flights. Crewed flights resume only after the problem has been resolved.
Of course, that scenario never happened, nor could it. The space shuttle has no capability for fully unmanned flights. It’s not just a matter of technology. NASA made sure the shuttle couldn’t fly itself, because the agency feared that such automation might undermine the primacy of the astronaut. Yet if NASA ever wants to see human beings walk on Mars, the cult of the astronaut must end.
The cult blossomed during the earliest days of NASA’s manned space program. Back in the late 1950s and early 1960s, the Mercury astronauts enjoyed rock-star popularity; they were walking embodiments of American individualism, military might, and middle-class values. Later astronauts, including Neil Armstrong and the other moonwalkers, had more education and engineering skill than their predecessors, but their technical prowess was overshadowed by their public personae, promoted by an eager NASA that sent them on world tours after their flights.
NASA’s engineering culture supported the centrality of the astronaut. Initially designated ”capsules,” crew vehicles were renamed ”spacecraft” to signify the human pilot’s mastery and control. The terminology matched the technology: The spacecraft’s controls, displays, and overall structure were designed with the pilot in mind. Yet many steps in the flights were automated, from the closed-loop launches to the predominantly automatic reentries. No human being could have handled all the complex tasks involved in orbital rendezvous and lunar landings without the aid of computers and fly-by-wire systems.
Some things that could have been automated, though, were not. During the Apollo era, engineers suggested landing the lunar module on the moon first without a crew, before exposing humans to the risky descent. NASA management rejected the plan. Engineers also designed the module so that it could land automatically. That feature was never used on any of the six Apollo landings; pilots switched it off, preferring to have their hands on the control stick. The space shuttle, likewise, has never flown an unmanned flight, nor has its automatic landing feature ever been used.