Facts about Jupiter

Jupiter Named by the Romans after their God and translating as God-father, and now commonly known asThe Red Giant’. The largest and most mysterious planet in the Solar System. It has some amazing features that no other planet comes close to

Firstly, here are some interesting and fascinating facts about Jupiter.

* Primarily made up of gas, rather than solid matter, it is one of four planets like this. Despite this, mostly gassy make up, Jupiter’s mass is approximately 2.5 times more than all the other 8 planets in the solar system put together. This means it is made up of over double the matter of the other planets.

* The atmosphere is built up of mainly Hydrogen (88-92%) with a dash of Helium (8-12%) However, there is a small percentage in between, made up of other elements, like water vapor, ammonia and methane among others.

* Jupiter’s sheer size is incomprehensible – at 1,317 times the size of earth, a radius of 71,492 kilometers – a diameter of 142,984 km. That’s roughly 22 times Earth’s diameter.

* It orbit’s the Sun at a median distance of around 778 Million km. It takes 11.86 Earth years to orbit around the Sun. Surprisingly, despite it’s size, Jupiter only takes just over 10 hours to rotate once on it’s axis.

* Jupiter’s Red Spot’ is a storm. A storm so vicious and inconceivable for us. It measures roughly 39,000 miles in diameter. It is considered a permanent feature of the planet, as it has been present since at least 1831.

* Jupiter has rings like Saturn. These are very difficult to see, but the inner and outer rings seem to be made up of dust and a third middle ring is made up of different materials from near by satellites – dust, rock and gasses.

* Considering the gravitational pull of the Planet, it is hardly surprising that it has so many satellites. Jupiter has 63 named moons. The major ones and most well known are Io, Europa, Ganymede and Callisto.

* Jupiter is entirely covered in clouds. Some are separated into bands, considered as the tropical regions, which are north and south of the equator. They rotate around the planet in opposite directions due to the hemispheres – like the way in which water will drain on Earth, depending on the hemisphere.

* Jupiter’s gravitational pull is about 22 times that of Earth, and temperatures are excruciatingly hot – the outer atmosphere reaching 153 degrees Celsius.


Due to the aforementioned gravitational pull, nothing man has made has yet been able to land on the planet. If a person were to fly and attempt to land on the planet, it is likely that their very being would cave in on itself, disintegrate and evaporate.
However, scientists and NASA have been able to send fly by and orbital space probes to collect data and images to further studies. In December 1973, NASA sent the first Pioneer mission to collect pictures of Jupiter and its moons. The Pioneer 11 spacecraft reached the closest distance from the planet, by flying only 34,000km from it. In 1979 the Voyager missions were the first to discover Jupiter’s rings as well as learn more about the four major moons. The Ulysses probe made 2 missions – in 1992 to collect data about the magnetosphere and once in 2004, whereby the fly by was at a much greater distance of 240 Million km away.
The new millennium saw the voyage of Cassini, who flew by Jupiter on its way to Saturn and in 2007, New Horizons reached its closest proximity to Jupiter while on its way to Pluto. It learnt of gravity data.
The Galileo Orbitor is the only mission to have orbited Jupiter, in 1995. The orbiter released an atmospheric probe in July 95 which entered Jupiter’s atmosphere in December 95. For almost an hour it sent data to NASA before gravitational pressure crushed and vaporized it.


As mentioned before, Jupiter’s main moons, first discovered by Galileo, are Io, Europa, Ganymede and Callisto. Their orbital process around the planet is unlike any other Every time Io makes four orbits, Europa makes two, and Ganymede makes one. Callisto orbits at an impressive distance of 1,882,709 kilometers from Jupiter – a testement to the strength of the gravity! The surfaces of these four moons have been studied in detail. Io’s surface is unexpectedly covered in smooth plains and mountains. There are even extensive active and violent volcanoes on this moon’s face. New Horizon’s provided images of a volcano erupting lava some 330 km above the surface.
Europa is a very icy moon. It is said to be one of the smoothest objects in the solar system. The surface appears marked with scratches. Several theories suggest these could have been made by volcanic eruptions or water geysers.
Ganymede’s surface is illustrated with old, cratered dark regions and younger, grooved areas with ridges.
Callisto is farthest of the four from Jupiter, and has been in the firing range for passing meteors, comets and other space debris. It surface is riddled with craters large and small.

47 satellites of Jupiter have a diameter of 10 km or less. These tiny moons have only been discovered since 1975. Aside from the four Galilean moons, the 59 others are split into several categories. The Inner group are four smaller moons with diameters of 200 km or less. These are considered the Regular moons’ with the Galilean’s.
The Irregular moons consist of:
Themisto – One moon in a category of its own!
Himalia Group – A cluster of moons, orbiting at around 11 million km from Jupiter.
Carpo – Another lone satellite.
Ananke Group – a group averaging a distance of 21,276,000 km from Jupiter.
Carme Group – orbiting at about 23,404,000 km from the Red Planet.
And, Pasiphae Group – A vague group of moons covering the most outer regions of the orbiting satellites.


Jupiter’s most famed characteristic, the Great Red Spot is a tumultuous storm. Nobody know what it is like, since nothing can get close enough to relay data. However, scientists have been able to study various aspects from afar.
This storm, measuring around 39,000 km across, can be visible from Earthly telescopes. It rotates once every six Earth days, and has been a feature for hundreds of years. Scientists have no reason to think it is going anywhere and so this may be a permanent storm! Nobody knows what the storm is made up of Tornadoes, Extreme winds, Lightning, Rain, Perhaps weather we have never experienced! If we could even conceive what it could be like, it might be scaled a category 100 hurricane, a F50 tornado. Who knows.
Other smaller, less turbulent storms, however still extremely violent, reside above the planet’s surface. In 2000, a smaller yet similar red Storm appeared in the southern hemisphere. This occurred when 3 white smaller storms, first sighted in 1938, merged to become one big storm. It is still active and has since turned to red, like it’s giant counterpart. It has been nicknamed Red Spot Junior!

Perhaps in the future, man will find a way to create a structure strong enough and powerful enough to survive Jupiter’s oppressive atmosphere and intense character. Perhaps we will be able to land a craft on the planet’s surface and learn about this world. The suggestion of life is an entertained thought, and maybe one day these theories could be supported..!