Mercury

"Named for the quick-footed messenger of the classical Roman gods, the planet Mercury is a heat-blasted rock orbiting closer than any other to our sun.With a daily temperature cycle of over 700 K, Mercury experiences greater temperature extremes than any other body in the solar system. Interestingly, though, the planet spins so slowly that it would be possible to walk in twilight forever, keeping pace with the sunrise in the relatively mild pre-dawn temperatures."