Based on the Phoenix lander, the craft is tasked with giving us a peek beneath the planet's surface, armed with tools that include a geodetic instrument from the Jet Propulsion Laboratory, which will be used to calculate Mars' rotation axis, a seismic wave sensor and a subsurface heat probe, to measure the planet's internal temperature.

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As the radioisotope decays, it produces heat energy that is converted by thermoelectric materials into the electricity that powers the space probe.

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