How Many Moons Does Jupiter Have?
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How Many Moons Does Jupiter Have?
If you’re wondering, “How many moons does Jupiter have?” you’re not alone! Scientists estimate that Jupiter has 67 moons and another 26 that are yet to be officially named. However, scientists believe that Jupiter may have up to 79 moons. Read on to learn about Jupiter’s moons and the disputed myths surrounding them. Despite these myths, the planet is incredibly beautiful and has a number of enchanting moons, including Io, Europa, Carme, and many others.
67 known moons
In our solar system, Jupiter has the largest number of moons of any planet. It has 67 known moons, including the four largest, called the Galilean satellites. The remaining 76 moons orbiting Jupiter are just 0.003% of its total mass. Jupiter’s moons are named after ancient Greek myths. Galileo Galilei first turned his telescope toward Jupiter in 1610.
The 67 known moons of Jupiter are categorized into two types: Galilean moons and Gigas, which are smaller, spherical satellites of Jupiter. While the Galilean moons were first discovered in 1610 by Galileo Galilei and Simon Marius, dozens of smaller satellites have been found since then. Several of the smaller moons have been given names after beloved people or asteroids.
Io
The three largest moons orbit the gas giant in a slightly different orbit than Jupiter itself. They are called Io, Ganymede, and Europa. Io is smaller than Mercury, and it orbits Jupiter at a distance of 222,000 km, or 138,000 miles. Discovered in 1979 by Stephen P. Synnott, the moon is the third largest in the Solar System. Its surface is covered with over 100 mountains, some of which are higher than Mount Everest.
The surface of Jupiter’s moons is constantly changing, and all three exhibit different types of geology. Ganymede has an ice crust and is exposed to 36 sieverts of energy per day – the same amount of energy that is absorbed by our own planet. Europa is more dynamic, and its ice crust is thinning and forming cracks. Io’s sulfur-covered surface and active volcanism indicate it once had a similar internal composition to Callisto.
Europa
Despite being slightly smaller than Earth’s moon, Europa is one of Jupiter’s largest moons. It has a smooth icy surface with little vertical relief, and only a handful of impact craters. The dark bands can be distinguished by the shadows they cast on its surface, and Europa’s high ridges and narrow valleys may be the result of a gradual spread of the ice that covers it.
Because of its eccentric orbit, Europa moves closer to Jupiter at its apojove and farther away at its perijove. This causes Europa to undergo libration, whereby its tidal bulge rocks from side to side as it orbits the gas giant. As it changes its orbital velocity, it deforms by 1 to 30 meters. The dissipation of strain energy causes the interior to warm and become more akin to the Earth than it is at Jupiter.
Carme
In the year 2011, astronomers discovered 67 moons orbiting Jupiter. These irregular satellites have a similar structure to larger moons but are not as massive. Rather, they were probably just rocks pulled into orbit by Jupiter. Despite these irregularities, Jupiter is the only planet in our solar system with more moons than Saturn. However, it is still unclear how many moons Jupiter really has. For now, we can only guess.
The answer to the question of how many moons does not lie solely in the number of satellites. Jupiter has three main types of satellites: regular and irregular. Regular satellites have a circular orbit around Jupiter, whereas irregular satellites have more eccentric orbits. Various theories suggest that irregular satellites are a result of Jupiter capturing a asteroid. However, other theories have suggested that irregular satellites are the result of collisions.
Callisto
There are more than 80 known moons orbiting Jupiter, not counting moonlets shed from the inner moons. The four largest are known as the Galilean moons, and their orbits have been known for centuries. The smaller ones orbit outside the orbit of Callisto and Jupiter, and they may be asteroids. Scientists continue to search for more satellites. They believe there are more than 600 moons on Jupiter.
Europa and Ganymede may have oceans, but these oceans are supposedly in contact with the rock on their bottoms. Callisto, on the other hand, may have no oceans. Ocean thickness is important for determining how much salt the water contains, and its distance from the icy sheets determines how habitable the moon is. Both Europa and Ganymede appear to meet the requirements. However, it is unclear if any of them are habitable.