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Planet or Star?

Planet or Star?
Planet or Star? Almost a star, giant Jupiter is the lord of the planets. It radiates four times as much energy as it receives from the distant Sun—energy from the slow contraction of its huge mass, 318 times that of Earth. But even Jupiter is not large enough to sustain a thermonuclear fire, so it represents a class of bodies intermediate between tiny, rocky planets and the huge, gaseous objects that collapse into stars. JPL / NASA