It is much farther from the sun than from Mars. It is 15 times farther than Mars, to be precise. But Jupiter can be seen from Earth with its eyes, just like Mars. This is because it is huge enough to hold all the other planets in our solar system inside. But just because it is big doesn't mean it is good for living. Above all, Jupiter has no surface to stand on.
If you go deep inside, you'll find a core, but the surface is covered with a layer of gas. Even if you step on it, the average temperature is over -100 °C, making it impossible for humans to survive. The best-known feature of Jupiter is a large red spot. It is a huge storm, like a hurricane. Nobody knows if this storm will last forever, but what is clear is that it has been storming continuously for the past 150 years. Even the astronomers who first observed Jupiter through telescopes discovered it quickly.
The size of the great red spot is constantly changing, and it is now four times the diameter of the Earth. One of Jupiter's interesting features is that it has a whopping 120 moons (scientists say there may be more moons we don't know yet). The person who discovered the four largest moons, Ganymede, Callisto, Europa, and Io, is a scientist named Galileo. Jupiter's moon, Ganymede, is the largest of Jupiter's moons at 5,120 kilometers in diameter. Like the Earth's moon, Ganymede is rocky, cold, covered in impact craters, and has many deep cracks and high valleys.
Callisto has craters that are similar to the moon but not that deep. Scientists think that this is because they are filled with ice. The new pits look brighter than other pits, which makes Callisto look spotty as a whole. Europa has ice and rocks, like the rest of Jupiter, but it is speculated that it has non-freezing water. Some astronomers suspect that the gravity of other moons may have caused the water to freeze. Io is known for having many volcanoes which are still active. Volcanoes are spraying sulfur rather than lava, and they are so large that they completely cover Io's surface every 100 years.
The rest of Jupiter's moons are small in size and have a Greek name.
Jupiter is the brightest star in the sky (without the sun, of course), so it is not difficult to find it in the night sky. The easiest time to observe Jupiter is when it comes closest to the Earth, and the first week of March 2004 was then. It comes closest to the Earth in the first week of April 2005, in 2006, in the first week of May, and in 2007, in the first week of July.
Like the biggest star in the solar system, Jupiter has the name of Jupiter, the greatest god in Rome. But it was just a coincidence, and the Romans didn't know how big Jupiter was. They named it the greatest god just because it shone the brightest.
Characteristics of Jupiter
Diameter: 143,884 km
Length of day (biological cycle): 9.8 hours
Length of one year (air cycle): 11.8 years on a global basis
Satellites: 16 (discovered up to 120, including so-called stars)
Surface temperature: -150C to -145C