Aphelion farthest distance from the sun : ,, miles ,, km. With four large moons and many smaller moons in orbit around it, Jupiter by itself forms a kind of miniature solar system. Jupiter has 79 known moons, which are mostly named after the paramours of Roman gods. Ganymede is the largest moon in our solar system, and is larger than Mercury and Pluto.
It is also the only moon known to have its own magnetic field. The moon has at least one ocean between layers of ice, although it may contain several layers of both ice and water, stacked on top of one another. Io is the most volcanically active body in our solar system. The sulfur its volcanoes spew gives Io a blotted yellow-orange appearance that looks kind of like a pepperoni pizza. As Io orbits Jupiter, the planet's immense gravity causes "tides" in Io's solid surface that rise feet meters high and generate enough heat for volcanic activity.
The frozen crust of Europa is made up mostly of water ice, and it may hide a liquid ocean that contains twice as much water as Earth does. Some of this liquid spouts from the surface in newly spotted sporadic plumes at Europa's southern pole.
NASA's Europa Clipper mission , a planned spacecraft that would launch in the s to explore the icy moon, is now in phase B the design stage. It would perform 40 to 45 flybys to examine the habitability of the moon.
Callisto has the lowest reflectivity, or albedo, of the four Galilean moons. This suggests that its surface may be composed of dark, colorless rock.
Jupiter's three rings came as a surprise when NASA's Voyager 1 spacecraft discovered them around the planet's equator in Each are much fainter than Saturn's rings. The main ring is flattened. From an average distance of million miles million kilometers , Jupiter is 5. One astronomical unit abbreviated as AU , is the distance from the Sun to Earth. From this distance, it takes Sunlight 43 minutes to travel from the Sun to Jupiter. Jupiter has the shortest day in the solar system. One day on Jupiter takes only about 10 hours the time it takes for Jupiter to rotate or spin around once , and Jupiter makes a complete orbit around the Sun a year in Jovian time in about 12 Earth years 4, Earth days.
Its equator is tilted with respect to its orbital path around the Sun by just 3 degrees. This means Jupiter spins nearly upright and does not have seasons as extreme as other planets do. With four large moons and many smaller moons, Jupiter forms a kind of miniature solar system. Jupiter has 53 confirmed moons and 26 provisional moons awaiting confirmation of discovery. Moons are named after they are confirmed. Jupiter's four largest moons — Io, Europa, Ganymede, and Callisto — were first observed by the astronomer Galileo Galilei in using an early version of the telescope.
These four moons are known today as the Galilean satellites, and they're some of the most fascinating destinations in our solar system. Io is the most volcanically active body in the solar system. Ganymede is the largest moon in the solar system even bigger than the planet Mercury. A liquid-water ocean with the ingredients for life may lie beneath the frozen crust of Europa, making it a tempting place to explore.
Discovered in by NASA's Voyager 1 spacecraft, Jupiter's rings were a surprise, as they are composed of small, dark particles and are difficult to see except when backlit by the Sun. Data from the Galileo spacecraft indicate that Jupiter's ring system may be formed by dust kicked up as interplanetary meteoroids smash into the giant planet's small innermost moons. Jupiter took shape when the rest of the solar system formed about 4. Jupiter took most of the mass left over after the formation of the Sun, ending up with more than twice the combined material of the other bodies in the solar system.
In fact, Jupiter has the same ingredients as a star, but it did not grow massive enough to ignite. About 4 billion years ago, Jupiter settled into its current position in the outer solar system, where it is the fifth planet from the Sun.
The composition of Jupiter is similar to that of the Sun — mostly hydrogen and helium. Deep in the atmosphere, pressure and temperature increase, compressing the hydrogen gas into a liquid. It takes Jupiter about 12 Earth years to orbit once around the Sun. This image of Jupiter was taken by Voyager 2 in The colors were later enhanced to bring out more details. Jupiter is named for the king of the gods in Roman mythology. The planet is enormous, the largest object in the solar system besides the Sun.
Like the other gas giants, it is much less dense than Earth. Astronauts trying to land a spaceship on the surface of Jupiter would find that there is no solid surface at all! Jupiter is made mostly of hydrogen, with some helium, and small amounts of other elements Figure below.
Deeper within the planet, pressure compresses the gases into a liquid. Some evidence suggests that Jupiter may have a small rocky core of heavier elements at its center. These bands rotate around the planet, but also swirl around in turbulent storms. This storm is more than three times as wide as the entire Earth. Clouds in the storm rotate in a counterclockwise direction, making one complete turn every six days or so.
The Great Red Spot has been on Jupiter for at least years, since astronomers could first see the storm through telescopes. Do you think the Great Red Spot is a permanent feature on Jupiter? How could you know?
The white storm just below the Great Red Spot is about the same diameter as Earth. Jupiter has a very large number of moons — 63 have been discovered so far.
Four are big enough and bright enough to be seen from Earth, using no more than a pair of binoculars. These moons — Io, Europa, Ganymede, and Callisto — were first discovered by Galileo in , so they are sometimes referred to as the Galilean moons Figure below.
The Galilean moons are larger than the dwarf planets Pluto, Ceres, and Eris. Ganymede is not only the biggest moon in the solar system it is even larger than the planet Mercury! This composite image shows the four Galilean moons and their sizes relative to the Great Red Spot. From top to bottom, the moons are Io, Europa, Ganymede, and Callisto. Sizes are to scale. Scientists are particularly interested in Europa because it may be a place to find extraterrestrial life.
What features might make a satellite so far from the Sun a candidate for life? Although the surface of Europa is a smooth layer of ice, there is evidence that there is an ocean of liquid water underneath Figure below. Europa also has a continual source of energy — it is heated as it is stretched and squashed by tidal forces from Jupiter. Numerous missions have been planned to explore Europa, including plans to drill through the ice and send a probe into the ocean.
The other is Jupiter , like a giant scoop of ice cream, coming in with a mean radius of 69, kilometres. The short answer is simple: Jupiter doesn't have enough mass to fuse hydrogen into helium. EBLM JAb is about 85 times the mass of Jupiter, about as light as a star can be - if it were any lower, it would not be able to fuse hydrogen either. But if our Solar System had been different, could Jupiter have ignited into a star?
The gas giant may not be a star, but Jupiter is still a Big Deal. Its mass is 2. It's just that, being a gas giant, it has really low density: around 1. But it's interesting to note the similarities between Jupiter and the Sun. The Sun's density is 1. And the two objects are very compositionally similar. By mass , the Sun is about 71 percent hydrogen and 27 percent helium, with the rest being made up of trace amounts of other elements. Jupiter by mass is about 73 percent hydrogen and 24 percent helium.
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