What Is the Spinning Motion of a Planet Around Its Axis?

Rotation and Day Length

• It takes the Earth 24 hours to complete one rotation on its axis, which is what gives you the sense of experiencing both day and night. The surface exposure of sunlight shifts as the Earth continues to spin on its axis, giving the perception of morning, noon and evening. Other planets have rotation periods of differing lengths than the Earth. Mercury, for example, has a day that is nearly 176 of our Earth days long due to the way it rotates on its axis.

Rotation and Axis

• Different planets are oriented on their axis at varying angles. This tilt causes them to receive uneven exposure to starlight, and is responsible for the seasons and length of a day for a planet. The Earth has a tilt of 23.5 degrees on its axis, which causes places like Alaska to have very long days during the summer and very long nights in the winter. In comparison, the planet Jupiter has a 3 degree tilt to its axis, which causes a more even distribution of sunlight across its surface.

Surface Effects of Rotation

• The force produced by the rotation of a planet on its axis can produce surface effects such as winds and water currents. The Earth's oceans experience the effect of the Earth's rotation as the jet stream -- a massive current running continuously throughout the oceans -- which causes climate anomalies to particular regions of the world. Great Britain, for example, is much warmer than it would normally be because the jet stream brings warmer waters near the island nation.

Rotation, Revolution and Seasons

• The length of time it takes a planet to revolve around the star or stars it is orbiting is called "revolution." When planets orbit a star, the combination of their rotation and revolution produce the effect of seasons. The Earth's seasons come from the effect of the the surface of the Earth receiving varying levels of sunlight due to the angle of the planet on its axis as it rotates. This causes the observer on Earth to experience varying amounts of sunlight throughout a one-year period. A year on Earth is 365 days because this is how long it takes the Earth to complete one revolution around the sun.