The 5 Coolest Moons of Jupiter

Jupiter, what a planet, one of the rarest and most interesting planets in our entire Solar System. The largest and arguably most beautiful planet, covered with gases and rich in coloring. But Jupiter has a unique quality that few know about; its massive collection of moons. We’re going to take a close look at the 5 Coolest Moons of Jupiter and find out what unique quality each possess.

Named after the ancient Roman god, Jupiter is the biggest planet in our Solar System. As a huge giant planet of gas and pressure, Jupiter depicts no possibility of life.

One of the most interesting facts about this massive planet is that it beholds a total of 63 moons; illustrating its very own ‘solar system’ in a sense. Jupiter is so large and has such a massive gravitational force; the planet naturally attracts large objects and either pulls objects in for a collision with its surface or draws large objects close enough that they remain in its orbit and become a moon.

The four largest moons are called the Galilean satellites, after Italian astronomer Galileo Galilei, who observed them as early as 1610. These large moons, called Io, Europa, Ganymede, and Callisto, are beauties and stunning in their own sense.

On the other hand, even the relatively smaller ones such as Amalthea, Kale, Aitne etc. are also equally scenic and amazing! In this article we’re going to explore the 5 Coolest Moons of Jupiter and see what interesting discoveries we can uncover along the way.

#5 Coolest Moon of Jupiter: Amalthea

Red in color, Amalthea is the third moon of Jupiter. Having been discovered by Edward Emerson Barnard in 1892, Amalthea is notably and interestingly not a spherical moon. Primarily, it was named for Amalthea in Greek mythology, who was known as the foster-mother of Zeus and nursed the god of the skies in his young childhood.

In addition to this, Amalthea is the largest of the inner moons of Jupiter and is most likely an asteroid captured by Jupiter. Taking a total of 0.49817905 Earth days to orbit Jupiter, it orbits its planet in a uniquely special way.



Image by NASA,


Amalthea’s Extraordinary Style of Orbit:

Amalthea is indeed a special moon in terms of the style of its orbit routine. Scientists have noted that Amalthea orbits Jupiter tidally. This means that at all times, the same side of Amalthea faces Jupiter. This is extraordinary as the other moons tend to rotate as well, but Amalthea stands its ground!

#4 Coolest Moon of Jupiter: Callisto

A large, dark and low density moon, Callisto is the eighth moon of Jupiter. It is covered with crater and breeds home to the Valhalla crater. In positional terms, it’s viewed as the outermost of the Galilean moons. Primarily, it takes Callisto 16.7 earth days to complete its orbit around its center planet Jupiter. However, Callisto’s way and style of orbit is also exceptional and different than other conventional moons of Jupiter.



“Callisto” by NASA/JPL/DLR(German Aerospace Center) – Licensed under Public Domain via Commons –


Callisto is a rebel in orbit:

Unlike other large moons of Jupiter namely Io, Europa and Ganymede; Callisto is not in sync with the otherwise traditional orbital gravitational pull. This indicates that there is less of a tidal heating, i.e. a buildup of friction, orbital and rotational energy that is given off as heat in the crust of the moons and planets involved. This heat leads to melting of the moon’s surface as well. But not in Callisto’s case! The reason it is less affected by Jupiter’s magnetosphere is that it orbits further away from the planet; rare and exceptional in its own way.

#3 Coolest Moon of Jupiter: Ganymede

A large, icy moon with a diameter of more than 3,100 miles and beautifully scarred with craters, Ganymede is the largest known moon of Jupiter. It’s larger than the planet Mercury and the dwarf planet Pluto in terms of diameter! In fact, Ganymede is admittedly the largest moon in our entire Solar System.



“Ganymede, moon of Jupiter, NASA” by NASA/JPL/DLR – Licensed under Public Domain via Commons –


Presence of Liquid Water:

Rigorous research and studies conducted in 2014 revealed that there is a possibility of existence of several saltwater ocean layers below the surface of this moon. This highlights the chances and possibilities of life on Ganymede: a rare and unheard of proposition until 2014.

#2 Coolest Moon of Jupiter: Europa

Illustrated as a huge, dense and icy moon, but with smooth surface, Europa is one of the coolest moons of Jupiter. Its surface is covered with long, crisscrossing pathways. It is estimated that nearly 4 billion years ago, numerous planets, moons and objects were bombarded heavily by asteroids and comets during the famous interval of the “Late Heavy Bombardment Period”. Thus, Europa has been termed the smoothest of all moons to exist in our Solar System.



“Europa-moon” by NASA/JPL/DLR – (TIFF image link). Licensed under Public Domain via Commons –


Europa, Smooth as Silk:

The surface of Europa is composed of frozen water, which results in it having the smoothest surface of any other objects in the Solar System. This means that it is not populated with large and bulky features, namely mountains or craters. More so, the reason Europa’ surface is especially smooth is because very few craters on the surface exist. Other scientists attribute its smoothness to the fact that since it is tectonically active and a relatively young moon, its surface is still unaffected and smooth in appearance.

#1 Coolest Moon of Jupiter: Io

Exceptionally shining bright with colors, attributable to molten sulfur, Io is a large, rocky and a volcanically active moon of Jupiter. In essence, Io lies in the doughnut-shaped plasma cloud around Jupiter, known as the “Io plasma torus” which has developed due to Jupiter’s extremely strong magnetic field.



“Io highest resolution true color” by NASA / JPL / University of Arizona – Licensed under Public Domain via Commons –


Io’s relation to Greek Mythology:

What makes Io the coolest moon of Jupiter is the myth and legend that led to its naming. The story goes that Io was actually a nymph loved by the Greek god of the skies: Zeus. The planet Jupiter was previously titled after this nymph back in the mid-1800s. However, according to the Greek mythology, Zeus turned Io into a cow to hide traces of his infidelity and cheating from his wife Hera. Thus, Io took its name after this Greek inspired story.

As the Solar System’s largest planet, Jupiter’s gravitational pull has attracted more moons than any other planet. Jupiter’s moons, though high in number, are each interesting and exciting in their own unique respect. Each has a rarity to them; and that is exactly what makes each one of them the coolest objects of the Solar System.



Featured image: NASA Solar System Exploration,

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