Jupiter is the fifth planet from the Sun and the largest in our entire solar system. It’s so massive that it’s more than twice as heavy as all the other planets combined! Made mostly of hydrogen and helium, Jupiter is a gas giant, which means it doesn’t have a solid surface like Earth or Mars. Instead, it’s a swirling ball of clouds, storms, and powerful winds, all moving across its thick atmosphere in colorful bands.

One of Jupiter’s most famous features is the Great Red Spot—a gigantic storm larger than Earth that has been raging for over 300 years. The planet also has a powerful magnetic field and gives off more heat than it receives from the Sun, showing that there's a lot of activity going on deep inside. Jupiter spins extremely fast, completing one rotation in just under 10 hours, which causes it to bulge at the equator and flatten at the poles.

But Jupiter isn’t just fascinating by itself—it also has a huge family of moons, with over 90 discovered so far. The four largest, known as the Galilean moons—Io, Europa, Ganymede, and Callisto—are each remarkable in their own way. For example, Europa may have a salty ocean beneath its icy surface, possibly harboring conditions for life, while Io is the most volcanically active body in the solar system. NASA’s Juno mission, currently orbiting Jupiter, is sending back incredible data about its atmosphere, magnetic field, and inner structure.

Jupiter plays a key role in our solar system. Its enormous gravity helps protect Earth by deflecting comets and asteroids, earning it the nickname “cosmic vacuum cleaner.” As the king of the planets, Jupiter continues to amaze scientists and skywatchers alike, offering endless opportunities for discovery and wonder.