What is the Planet Jupiter? | Types, Definition, Structure, Function & Facts

What is the Planet Jupiter?

Jupiter is the largest planet in the solar system and the fifth planet from the sun. It is more than 300 times heavier than Earth and more than twice as massive as all the other planets combined.

Jupiter is known as the gas giant planet. Indeed, its surface consists of a thick layer of hydrogen gas. Deep inside the planet, under the gas, the pressure becomes so great that the hydrogen turns into a liquid and eventually into a metal. Beneath the hydrogen is a rocky core roughly the size of planet Earth.

Highlights of Planet Jupiter:

Moons	79 (and growing)
Mass	318 times the mass of Earth
Diameter	88,846 miles (142,984 km)
Year	11.9 Earth years
Day	9.8 hours
Average Temperature	minus 162°F (-108°C)
Distance from the Sun	5th planet from the sun, 484 million miles (778 million km)
Type of Planet	Gas Giant (composed mostly of hydrogen and helium)

Weather on Jupiter

Jupiter’s surface is very violent with storms, winds, thunder, and massive hurricane-like lightning. A storm on Jupiter, known as the Great Red Spot, is three times larger than Earth. The Great Red Spot has raged for hundreds of years. The energy that powers Jupiter’s storms does not come from the sun, but from radiation produced by Jupiter itself.

The Moons of Jupiter

Jupiter is home to a number of interesting moons, including Ganymede, Io, Europa, and Callisto. These four satellites were first discovered by Galileo and are known as Galilean satellites. Ganymede, the largest moon in the solar system, is larger than the planet Mercury. Io is covered with volcanoes and lava.

On the other hand, Europa is covered with ice and has a huge saltwater sea under the ice. Some believe there is a high probability that life could exist in the seas of Europe. The many different moons around Jupiter make it a fascinating place to explore.

How does Jupiter compare to Earth?

Jupiter is very different from Earth. First, there is no foothold, the surface is gas. Second, Jupiter is 300 times the size of Earth and has (at least) 79 moons compared to just one on Earth. Plus, Jupiter has a 300-year-old storm that will engulf the Earth without even knowing it. I’m glad we don’t have such a storm!

How do we know about Jupiter?

As the 3rd brightest object in the night sky, humans have known the existence of Jupiter thousands of years ago. Galileo first discovered Jupiter’s four largest moons in 1610, and others claim to have discovered the Great Red Spot soon after. In 1973, the space probe Pioneer 10 flew by Jupiter and provided the first close-up images of the planet. The Pioneer probes followed by Travels 1 and 2 gave us the first close-up images of Jupiter’s moons. Since then, there have been many more flybys of Jupiter. The only spacecraft to orbit Jupiter was Galileo in 1995.

Interesting Facts about the Planet Jupiter

In Roman mythology, Jupiter was the king of the gods and the god of the sky. He is the equivalent of the Greek god Zeus.

It is the fastest rotating planet in the solar system.

Jupiter has three very faint rings.