Which planet in the solar system has the shortest day?

That rapid spin belongs to the largest planet of all. Jupiter is 11 times wider than Earth, and if it were a hollow shell, 1,000 Earths could fit inside. NASA offers a handy comparison: if Earth were the size of a grape, Jupiter would be roughly the size of a basketball. The planet orbits at an average distance of about 778 million kilometres from the Sun, or 5.2 astronomical units, so sunlight takes about 43 minutes to reach it. In make-up it resembles the Sun, being mostly hydrogen and helium. Its best-known feature is the Great Red Spot, a giant storm bigger than Earth that has been observed for more than 300 years. So a planet large enough to swallow a thousand Earths still turns fully round in less than ten hours, while its long, slow orbit around the Sun takes roughly a dozen of our years to complete.