The Gas Giant
When you think of the largest planet in the solar system, many of you will probably think about the majestic planet of Jupiter. Jupiter is characterized by its swirling storms, dozens of natural satellites, and powerful magnetic field, and has some other surprising facts that make it even more mysterious. With that in mind, here are 5 facts about Jupiter.
NASA Hubble Space Telescope on Unsplash
1. The Name
Jupiter is named after the chief deity in ancient Roman mythology. The name is fitting, as the planet is the largest in our solar system. Just as the god Jupiter was king of the Roman gods, the planet is the undisputed giant of the solar system, and more than twice as massive as all of the other planets in the solar system combined.
2. Moons
Jupiter has 95 known moons, and the combination is sometimes called a mini solar system. Galileo Galilei discovered its four biggest, Io, Europa, Ganymede, and Callisto in 1610. They are some of the solar system's most fascinating worlds. Io is volcanically active, Europa may have an ocean of water under its icy crust, Ganymede is bigger than the planet Mercury, and Callisto has evidence of mild geologic activity.
NASA / Jet Propulsion Lab-Caltech / SETI Institute on Wikimedia
3. Rings
Jupiter's faint rings were a surprise discovery made by NASA's Voyager 1 spacecraft in 1979. Astronomers had previously believed that Saturn was the only planet to have rings. Jupiter's rings are made of dark, fine particles that are almost invisible unless they are backlit by the Sun. They are believed to be made of dust that has been kicked up as the result of meteoroids colliding with Jupiter's small inner moons.
4. Structure
Like the Sun, Jupiter is primarily composed of hydrogen and helium. Under the intense pressures found deep within Jupiter, hydrogen gas converts to liquid and, farther down, to a metallic state that is capable of conducting electricity, thus creating Jupiter's strong magnetic field by means of a planetary dynamo. Recent measurements by NASA's Juno spacecraft suggest that Jupiter has a "fuzzy" core that is partially mixed up with the surrounding metallic hydrogen layer instead of a dense core distinct at the center.
5. Surface
Jupiter is a gas giant, so it doesn't have a solid surface. It's made of clouds and is mostly hydrogen and helium. A spacecraft would never reach the surface; it would be crushed and vaporized by the heat and pressure.
