Planet Jupiter | The Solar System’s Gas Giant

Cool Facts About The Solar System’s Giant Planet!

• Jupiter has been known since ancient times and is typically the third brightest object in the night sky after the Moon and Venus.
• Jupiter has over 318 times the mass of Earth, but if it was 75 times more massive, nuclear fusion in its core would begin turning the gas giant into a star!
• Despite being only 0.1% the mass of the Sun, the centre of gravity between it and the Sun lies just above the Sun's surface. This is the only planet for which this is true.
• Jupiter is 11 times wider than Earth and over 1,320 Earth’s are able to fit inside the gas giant.
• Despite being the biggest planet in the Solar System, it has the shortest day, completing an orbit every 9 hours and 55 minutes. This causes it to have a slightly ‘flattened’ shape.
• Jupiter spins nearly upright as it orbits the Sun, so doesn’t experience seasons like the other planets do.
• The planet is believed to have a solid core of heavy elements, but is mostly made up of swirling gases and fluids like hydrogen and helium (similar to what the Sun is made of).
• Jupiter’s appearance is dominated by uniquely colourful bands of cloud and swirling spots. Many of the bands move in opposite directions to one another.
• The ‘Great Red Spot’ is a gigantic storm which has been ragging since detailed observations of Jupiter were first made nearly 200 years ago.
• Jupiter is orbited by at least 69 moons, most small captured asteroids, but the four Galilean moons are among the most interesting in the Solar System!
  • The inner most Galilean moon ‘Io’ is the most volcanic object in the Solar System!
  • The bright icy moons Europa and Callisto may harbour deep oceans under their icy crusts.
  • And the biggest of the Galilean moons, Ganymede, is larger than the Planet Mercury!
• Jupiter is known to have the largest magnetic field of any planet. It is between 15 and 50 times stronger than Earth’s and results in a band of radiation close to the planet which is hazardous to spacecraft.
• This powerful magnetosphere also creates some of the Solar System’s more spectacular auroras near the planets poles.
• In 1994, something truly amazing happened to Jupiter. Twenty fragments of the comet Shoemaker-levy 9 collided with planet. These impacts created enormous explosions and left dark clouds the size of Earth!
• A total of 9 space probes have visited Jupiter, most making flybys - Pioneer 10&11, Voyager 1, Voyager 2, Ulysses, Cassini-Huygens and New Horizons. Two spacecraft (Galileo & Juno) entered orbit to study Jupiter & its moons up close.
• Two future missions are planned to visit Jupiter in the 2020’s (ESA’s JUICE & NASA’s Europa Clipper) to study the frozen Galilean moons which may have habitat environments in their subsurface oceans. I can’t wait to see what they discover!