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From the perspective of distant stars, Mars completes a full rotation in 24 hours, 37 minutes, and 22.7 seconds—its sidereal day. Its solar day—the interval between successive sunrises for an observer on the surface—lasts 24 hours, 39 minutes, and 35.2 seconds. The slight difference reflects Mars’ orbital speed and axial tilt.
Earth’s sidereal day is 23 hours, 56 minutes, and 4 seconds, while its solar day is a clean 24 hours. In comparison, a Martian sol (solar day) is 24 minutes and 35 seconds longer than an Earth day. In sidereal terms, the Martian day is about 41 minutes longer than Earth’s.
