Jupiter, the most massive planet of the solar system and the fifth in distance from the Sun. It is one of the brightest objects in the night sky; only the Moon, Venus, and sometimes Mars are more brilliant. Jupiter is designated by the symbol ♃.
When ancient astronomers named the planet Jupiter for the Roman ruler of the gods and heavens (also known as Jove), they had no idea of the planet’s true dimensions, but the name is appropriate, for Jupiter is larger than all the other planets combined. It takes nearly 12 Earth years to orbit the Sun, and it rotates once about every 10 hours, more than twice as fast as Earth; its colourful cloud bands can be seen with even a small telescope. It has a narrow system of rings and 92 known moons, one larger than the planet Mercury and three larger than Earth’s Moon. Some astronomers speculate that Jupiter’s moon Europa may be hiding an ocean of warm water—and possibly even some kind of life—beneath an icy crust.
Jupiter has an internal heat source; it emits more energy than it receives from the Sun. The pressure in its deep interior is so high that the hydrogen there exists in a fluid metallic state. This giant has the strongest magnetic field of any planet, with a magnetosphere so large that, if it could be seen from Earth, its apparent diameter would exceed that of the Moon. Jupiter’s system is also the source of intense bursts of radio noise, at some frequencies occasionally radiating more energy than the Sun. Despite all its superlatives, however, Jupiter is made almost entirely of only two elements, hydrogen and helium, and its mean density is not much more than the density of water.
Knowledge about the Jovian system grew dramatically after the mid-1970s as a result of explorations by three spacecraft missions—Pioneers 10 and 11 in 1973–74, Voyager 1 and 2 in 1979, and the Galileo orbiter and probe, which arrived at Jupiter in December 1995. Continue reading from Britannica
Facts about Jupiter (European Space Agency)
Here's why Jupiter's tally of moons keeps going up and up (NPR)
Jupiter: A guide to the largest planet in the solar system (Space.com)
Jupiter, the planet with a planetary system of its own (The Planetary Society)
Jupiter Facts for Kids (Kiddle)
Planet Jupiter facts and information (National Geographic)
Planet Jupiter Facts - Interesting Facts For Kids & Amateurs (The Planets)
Our solar system formed about 4.5 billion years ago from a dense cloud of interstellar gas and dust. The cloud collapsed, possibly due to the shockwave of a nearby exploding star, called a supernova. When this dust cloud collapsed, it formed a solar nebula—a spinning, swirling disk of material.
At the center, gravity pulled more and more material in. Eventually the pressure in the core was so great that hydrogen atoms began to combine and form helium, releasing a tremendous amount of energy. With that, our Sun was born, and it eventually amassed more than 99 percent of the available matter. Continue reading from NASA