Mercury rotates slowly. One rotation takes nearly 59 Earth days to complete. However due to an orbital-rotational resonance ratio of 3:2, a fictitious observer on Mercury would see that a solar day

Why does Mercury not rotate?

Mercury does not rotate on its axis smoothly, like a record, but experiences regular fluctuations in speed over an 88-day cycle – a year on the closest planet to the sun. These oscillations, or librations, are caused by the planet’s interactions with the sun as it moves around the star.

What way does Mercury rotate?

All of these planets orbit the Sun in a counterclockwise direction, and Mercury, Earth, and Mars rotate counterclockwise around their axes.