As of this moment, the most advanced robotic planetary surface probe ever constructed by humankind is in the early stages of unraveling the untold mysteries of the Red Planet. The Mars Science Laboratory mission has reached its most momentous phase: successfully deploying the Curiosity rover onto the Martian surface.
And Curiosity is a serious piece of work.
First, there was Curiosity’s landing, which involved ballistic reentry, a massive parachute, retrorockets, and a flying crane. Every system had to function in perfect sequence, after traveling millions of miles in the cold soak and radiation heat of interplanetary space, culminating in a dramatic, tension-fraught touchdown worthy of a Hollywood movie.
What that touchdown delivered was, without exaggeration, a nuclear-powered robot car equipped with a laser cannon. Seriously.
It all begins with Curiosity’s power plant, a radioisotope thermoelectric generator (RTG). Satellites and space probes have used RTGs for decades, but no planetary rover has ever been equipped with one before. An RTG isn’t a nuclear reactor, but a series of thermocouples wrapped around slugs of non-fissile Plutonium-238, which gives off stable amounts of heat that are converted into electricity (or redirected to keep rover systems from freezing). Because Curiosity uses an RTG rather than relying on solar power like previous Mars rovers, Curiosity can carry more instruments, and instruments that draw more power.
Like an infrared laser drill that vaporizes rock samples.
Every aspect of Curiosity is designed to maximize the amount of data relayed back to NASA scientists. Well, almost every aspect. At least one design element–Curiosity’s wheels–combine function and whimsy, as they contain an inside joke.
WHAT INSIDE JOKE IS HIDDEN IN THE WHEELS OF THE MARS CURIOSITY ROVER?