Jupiter is the fifth planet from the Sun and the largest in the Solar System, Jupiter is named after the Roman god of sky and thunder in fact Jupiter was the “King of the Gods” the equivalent of the Greek God Zeus. Jupiter is the fourth brightest object in our solar system is visible to the naked eye and was first recorded by the ancient Babylonians in around the 7th or 8th century’s BC. It couldn’t be more accurately named because Jupiter is massive, I mean really massive. In fact if Jupiter got any more massive, it would actually shrink due to the gravitational effects causing it to pull in on itself. Jupiter mass is incredibly two and a half times that of the combined mass of all other planets in the entire solar system. Jupiter is almost like its own mini solar system. It has four main large moons, Io, Europa, Ganymede, and Callisto, however Jupiter has 67 confirmed moons which are in turn split into three categories, Inner, Galilean and Outer. It even has a faint ring system around it. I will come back to these moons and ring system at another time to discuss in more detail.
A Jovian day takes just under 10 Earth Hours making it the fastest rotating body in our Solar System. However it will take 12 Earth Years for Jupiter to complete one orbit around the sun! This means Jupiter has only made two complete revaluations of the sun in my lifetime! Jupiter is more than five times farther than the sun than Earth. That’s 484 million miles (778 million kilometres) or 5.2 Astronomical Units. However its presence is felt throughout the solar system acting like a cosmic shield that eats up or sling shots away any would be comets or asteroid’s that would collide with earth. Jupiter’s gravity of is only 2 and a half times what it is on Earth, due to it being made up of gases. Jupiter is the first of the gas giants that live in the outer solar system composed 89.8 percent molecular hydrogen, 10.2 percent helium, minor amounts of methane, ammonia and water. Unlike the planets Mercury, Venus Earth and Mars it does not have a solid core the gaseous material it is made from simply gets denser with depth. The colourful cloud belts of Jupiter are arranged in dark and light zones created by strong east-west winds in the planet’s upper atmosphere which are made of ammonia crystals and sulphur traveling at speeds more than 400 miles an hour (640 kilometres per hour). The huge “Red Spot” that appears in the cloud belt is an enormous storm that has been raging for over 300 years. This storm is big that three Earth’s would fit inside of it.
There have been a lot of missions to Jupiter beginning with NASA’s Pioneer 10 spacecraft in December 1973 followed by then Pioneer 11 in December 1974. Voyager 1 and 2 in 1979 where the last until Ulysses arrived in February 1992. Cassini made a flyby in 2000, on its way to Saturn. And finally, NASA’s New Horizons spacecraft made its flyby in 2007. Below are a few links to the sites I gathered my information on but I would like to advise you to check out www.astronomycast.com and www.universetoday.com Photo Credit: Reto Stöckli, Nazmi El Saleous, and Marit Jentoft-Nilsen, NASA GSFC.