Jupiter

Jupiter is the largest planet of  the Solar System. If  Earth were placed on the face of Jupiter, it would look like a 50 paise coin on a dinner plate.  It weighs more than  twice as  much as  all the other eight planets put together. It has sixteen known satellites. Jupiter is not only the biggest planet bur also the liveliest. It is full of mysteries and surprises. Its highest clouds are mainly crystals of  frozen ammonia gas at a temperature of about -140⁰c.  It is veiled in a turbulent, gaseous atmosphere made up of hydrogen and helium with significant amounts of ammonia and methane. The atmosphere. reaches  thousands of kilometers deep to  the surface. It gradually thickens into a churning liquid  due  to  the  immense pressures  scientists assume that  it  finally turns into a liquid metallic core. At its centre, Jupiter has a small  rocky core where temperatures probably reach 20,000⁰C,  about three times the temperature of  the Sun's surface. There may also be iron, silicon and other heavy elements  in the rocky core. Jupittr seems  to be  more  like  the Sun  in  its composition than the other planets.  

dropped through it. Sometimes  it becomes pale plnk in colour and at other times a fiery orange red. For long, the Great Red Spot puzzled the astronomers. The Pioneer and Voyager missions to Jupiter revealed that  the Red Spot is a huge cyclonic disturbance in the atmosphere. Jupiter is mainly a quick-spinning ball of gas and liquid with no solid surface. It also emits radio waves. Its composition, size and the number of moons gave rise to the idea that Jupiter is not a planet but rather a star with a "sdar system" of  its own, that did1 not start 'burning'.  It is estimated that  if  Jupiter,were  just  ten times heavier, it could have started to produce its own energy like the Sun. Jupiter's four largest satellites, 10, Europa, Ganymede and Callisto are called the Galilean satellites after Galileo, their discoverer. They are fascinating worlds in themselves. Io,,of diamw  3240 km,  is almost like a fireball'with frequent-volcanic eruptions. Beyond 10 are Europa, diameter 3120 Km,  Ganymede, diameter 4900 km and Callisto, diameter 4U0  lan.  Europa is thought to'& made-up  of  frozen ice.  - Ganymede and Callisto have a thick icy covering on them. The remaining satellites  of Jupiter have not been so well studied.