Moving away from the rocky planets of the inner solar system the first planet in this region is the king of the planets – Jupiter. This is especially fitting as Juno has just entered orbit of Jupiter at the start of it’s mission to find out more about this giant. Veiled in colourful clouds of hydrogen and Helium it is the largest and the most vivid of all the gas giants. With 67 known moons in stable orbits, Jupiter has the largest amount of moons of any planet in the solar system and with rings only discovered in the 1970’s too there is so much to Jupiter that it will be impossible to cover it all in this piece.
Facts about Jupiter
Some of the key facts about Jupiter and how it compares with Earth:
- Diameter 139,800km (11 x Earth’s)
- 1 Jupiter Day = 9 hours long.
- 1 Jupiter year = 12 years.
- Atmosphere = 75% Hydrogen, 25% Helium.
- Volume = 1,300 times that of Earth.
- Distance from the Sun = 5.4 x further than Earth.
- Jupiter has 67 moons.
- Three Earth’s could fit into the ‘Great Red Spot’.
- Mas is over 317 x Earths mass (This is not as dense as Earth when considering it’s volume)
Because there are so many moons hurtling around Jupiter, covering them all is better served by looking at this link on Wikipedia on Jupiter’s moons:
There are the four major Galilean moons, discovered by Galileo (hence the names). These are the four largest moons that are visible with an ordinary pair of binoculars or a small telescope. Despite their similar locations, these worlds could not be more different.
IO is the most volcanic worlds in the solar system. IO’s surface is a barren sulfur rich surface, spewed from more than 400 volcanoes all over the moon. The are generated from the kneading effect Jupiter’s gravity has on the small world.
Europa, which is about the size of our moon has the smoothest surface of any known object in the solar system. It’s makeup is thought to be made of Nickel and Iron, but it’s the frozen water surface that has intrigued scientists for years. The frozen surface it expected to hide a sub surface ocean which could harbour life.
It’s surface is almost crater less, implying that it’s surface is frequently changing and re-freezing in order to keep it’s smooth nature. The surface is criss-crossed with giant ice cracks .
Ganymede is the largest of Jupiter’s moons and is the only moon to have a magnetosphere. It has a roughly equal silicate rock / water ice makeup. It’s larger than Mercury, but with less mass. The origins of the lighter regions seen on Ganymede are unknown, but are suspected to be the result of tectonic activity.
Calliso is a moon made mostly of rock and ice, with little evidence of geologic activity on it’s thought it’s surface has been made completely from impacts of other objects. Callisto is the third largest moon in the solar system and Jupiter’s second largest moon.
Holst’s musical inspiration for Jupiter, is big, loud, bold and Jovial. Exactly fitting for the king of our planets.
Yesterday on the 4th of July 2016 Juno arrived at Jupiter and entered obit around the planet. It’s going to be taking measurements to find out more about what the planet is made of, this is going to give us clue to how the planet was formed. Currently several theories present about the planets format, data from Juno should help us pick one, or come up with another theory.
Jupiter has been visited a number of times with unmanned probes, the pioneer missions being the first, with Voyagers 1 and 2 following after and giving us far more data about the planet and it’s moos, also discovering the Jupiter is a planet with rings.
Since then, Cassini has flown past on the way to Saturn New Horizons also paid Jupiter a fleeting visit on it’s way to Pluto. The only mission to orbit Jupiter is the Galileo, which orbited Jupiter for seven years and gathers data on it’s atmosphere and moons before being deliberately aimed into the Jovian atmosphere, gathering a wealth of data before being crushed and vaporised by the intense pressure and heat.
Hubble has also bee able to gather data on Jupiter, these images showing the amazing detail Hubble can bring us of the planets by itself.
Keep an eye out for Jupiter on Juno – also they’re opening much of Juno’s camera to the public, enabling them to take and colour correct the pictures that they capture. This means space exploration is getting interactive and Jupiter is going to be more interesting.
No ownership claimed on images or materials – Credit – NASA