All the major planets apart from Mercury and Venus have moons , and if we are talking about planets like Saturn or Jupiter, they have dozens of them orbiting around them. From Jupiter we are closer to its four main moons or Galilean moons and there are quite a few moons in our solar system that are frankly extravagant.
Triton (Neptune)
We traveled to Neptune to meet one of its moons: it is one of the coldest stars in our cosmic neighborhood. Triton is 4.5 billion kilometers from the Sun and is the largest moon of this planet (it has 13 moons). It’s a moon full of quirks because it orbits in the opposite direction to Neptune’s rotation to begin with, making it the only large moon within our solar system with a retrograde orbit. Temperature-wise, it is so frigid that much of its nitrogen-rich atmosphere is actually frost. Shall we travel to Triton? NASA’s Trident mission could be a possibility. This mission has a proposed launch date of October 2025. If definitively approved, the spacecraft would arrive at Triton in June 2038.
Callisto (Jupiter)
Callisto is the outermost of the Galilean moons of Jupiter. Just slightly smaller than Mercury, it holds the title of being the most cratered object in the entire solar system. There are craters everywhere. And why does it have so many craters? This is because the giant planet’s gravity exerts a powerful influence, disrupting the orbits of passing comets and often causing them to crash. The result is this dense landscape of craters layered over eons.
Dactyl (Ida)
Asteroid Ida has a small curious-looking moon (many say it looks like a potato) about 1.5 kilometers in diameter called Dactyl. This moon was discovered on February 17, 1994 orbiting at a distance of approximately 90 kilometers from the asteroid named Ida. It is currently the only known moon orbiting an asteroid. It is part of the asteroid belt objects between Mars and Jupiter. The moon is quite small, we have already seen, but it is spherical, something that is disconcerting, because as something so insignificant (astronomical speaking) it has been able to become a spheroid.
Hyperion (Saturn)
The fluffy and chaotic moon of Saturn is our next protagonist. It is one of the smaller moons of Saturn (and it will not surprise us that you remember the first novel of the tetralogy The Songs of Hyperion by Dan Simmons). It is not spherical, and is likely to be a fragment of a much larger ancient moon destroyed by an impact in the early solar system, astronomers say. The moon has a very low density, almost half that of water, giving Hyperion its porous, spongy appearance.
Phobos (Mars)
Phobos is the larger of the two Martian moons (the other is Deimos). This irregularly shaped moon orbits the red planet three times a day but, considering that each year it moves 1.8 centimeters closer to Mars, in about 50 million years the moon will collide with the planet and there are studies that show that after this gravitational pull, Phobos would become a ring for the red world.
Io (Jupiter)
This moon of Jupiter represents a true hell within the solar system. Although it is slightly larger than our Moon, it has temperatures that average 202 degrees below zero: cold enough for sulfur dioxide to freeze and form snowfields. Of course, another of the characteristics that attract attention are its hundreds of volcanoes that release lava kilometers away and their plumes of sulfur that also rise in the heights. It is the most geologically active object in the solar system.
Referencia: American Astronomical Society / NASA
