**Samuel Chiltern**answered

Jupiter rotates on its axis at a speed of 45,300 kilometres an hour at the equator, which is equivalent to 12.6 kilometres a second.

Jupiter has the fastest rotational speed of all the planets in the Solar System, and this causes the planet to 'flatten', producing a bulge at the equator.

In fact, the diameter of the planet measures 9,275 kilometres more around the equator than it does from pole to pole.

Like many measurements in astronomy, this speed is an average. At its polar extremes, Jupiter takes about five minutes longer to rotate than at its equator.

This rapid speed of rotation produces an extremely short day on Jupiter, lasting only 9.925 hours (9 hours, 55 minutes) - less than half the length of an Earth day.

In spite of its particularly short day, a Jovian year is actually quite long, compared to any of the inner planets. It takes Jupiter almost 12 Earth years to go round the Sun. This is equivalent to 10,475 Jupiter solar days - which makes for a very long year indeed!

Jupiter has the fastest rotational speed of all the planets in the Solar System, and this causes the planet to 'flatten', producing a bulge at the equator.

In fact, the diameter of the planet measures 9,275 kilometres more around the equator than it does from pole to pole.

Like many measurements in astronomy, this speed is an average. At its polar extremes, Jupiter takes about five minutes longer to rotate than at its equator.

**The Peculiarities of the Jovian Calendar**This rapid speed of rotation produces an extremely short day on Jupiter, lasting only 9.925 hours (9 hours, 55 minutes) - less than half the length of an Earth day.

In spite of its particularly short day, a Jovian year is actually quite long, compared to any of the inner planets. It takes Jupiter almost 12 Earth years to go round the Sun. This is equivalent to 10,475 Jupiter solar days - which makes for a very long year indeed!