1. Education
You can opt-out at any time. Please refer to our privacy policy for contact information.

Facts About Jupiter


Jupiter is the largest planet by volume and by mass in the solar system. While there are other planets in the galaxy that are even bigger, nothing short of the Sun commands the same presence in our neck of the woods. In addition to its raw size, there are many interesting facts about Jupiter, many of which may surprise some people. So read on below for all the best facts about the "king of the planets".

1. Jupiter's Famous Red Spot is a Storm that is Larger than the Entire Earth.

Antonio M. Rosario/ Stockbyte/ Getty Images

The giant red spot on Jupiter is one of the planet's defining traits. It is known to have existed for at least 300 years, and hasn't shown any signs of dying down. And while it appears small compared to the immense size of its host planet, the storm would swallow the Earth whole without even a second thought.

2. Jupiter Has Rings.

This one usually surprises people. When we think of planetary rings, we typically think of Saturn. But all of the Jovian planets (literally: planets that are like Jupiter) have rings about them. Though, like Jupiter, they are usually very difficult to see. Specifically, it is unlikely that you would be able to spot them, even with a fairly powerful telescope. Usually, they pop up when viewed through telescopes of different wavelengths, or when using a tool that actually blocks out the giant planet itself.

3. Jupiter Has the Strongest Gravity of all the Planets in the Solar System.

The Sun has an even stronger gravitational pull, but among the planets Jupiter is once again king. With an average surface gravity in excess of 3 times the Earth's pull, Jupiter sure sucks quite hard. This is made possible from the nearly 318 Earth masses crammed into its volume.

4. Jupiter is the Fastest Rotating Planet in our Solar System.

A day on Earth lasts about 24 hours. On Jupiter, however, a day passes in less than 10 (9 hours and 55 minutes more precisely). This is even more impressive given the planet's size.

5. Jupiter Actually produces its Own Radiation.

We see all of the planets in our solar system because our Sun emits great amounts of light (radiation) that is then reflected by the other heavenly bodies. And for the most part, the Sun is the only body that produces its own energy (radiation). Notice I said for the most part. That is because Jupiter (and Saturn through a somewhat similar process) actually produces energy. The theory goes that Jupiter is actually shrinking and by doing so releases gravitational energy. While this release of energy isn't enough to make the planet light up like the Sun, it is a non-trivial amount nonetheless.

6. Jupiter Has More than 60 Moons.

I say more than 60 because, well, we don't yet know exactly how many the gas giant has. As we take more and more detailed measurements we confirm the existence of more and more of these tiny orbiting rocks. Many of them may be captured asteroids from the asteroid belt. Others, like those closest to Jupiter, may have formed in orbit during the early Solar System. Likely there is more than 70 objects that will eventually be classified as moons of Jupiter.

7. Jupiter's Moon Ganymede is the Largest Moon in the Solar System.

We typically think of our own Moon as being pretty big, but the title of the biggest in the solar system goes to Ganymede.

8. Jupiter is Visible to the Naked Eye

Not only can you see Jupiter with the naked eye on a clear night, but the giant planet will appear as one of the brightest objects in the sky.

9. Jupiter's Magnetic Field is 14 Times Stronger than Earth's

Because of this powerful magnetic field, brilliant auroras, like those seen near Earth's poles are visible with the right type of equipment.

10. Hubble Watched as a Comet Slammed into Jupiter

This was a historic event. Never before witnessed, a team of scientists were able to watch as fragments of the comet Shoemaker-Levy 9 crashed through the atmosphere of Jupiter. The result was the appearance of a dark spot where the impact occurred.

11. BONUS: Jupiter Will Never Become a Star

There are discussions in classrooms across the country every year that Jupiter could be classified as a failed star. While there is an ouce of truth to this, Jupiter is quite far from becoming a star. A star is said to be born when the core of the object becomes so dense and hot that nuclear fusion is ignited. This process powers the star and makes it "shine". While Jupiter has all the basic ingredients, it doesn't have nearly enough mass to create the necessary core conditions. In fact, Jupiter would have to have at least 70 times more mass than it currently does to achieve core fusion.

©2014 About.com. All rights reserved.