Venus rotates on itself in about 243 Earth days. It orbits the Sun in about 225 days. It can be said that its rotation lasts longer than its year.
But imagine an observer who measures the time between two passes of the Sun in the same place in the sky. It would not find 243 Earth days: the Venusian solar day lasts about 117 days. Rotation and orbital displacement combine, with rotation in the opposite direction to that of most planets.
The strangeness of Venus is real. The small fall is in the vocabulary: before saying that a day exceeds a year, it is necessary to specify which day we are talking about. Even a fact as familiar as a day changes meaning when you change planet.
What we know
Sidereal rotation: about 243 Earth days. Solar day: about 117. Orbital period: approximately 225.
To go to the source
References consulted on September 20, 2026. Linked pages may be in another language.
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