Largest moons in the solar system
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Largest Moons in the Solar System: Key Facts and Rankings
Ganymede: The Largest Moon in the Solar System
Jupiter’s moon Ganymede is the largest moon in the solar system. It is even larger by volume than the planet Mercury and is unique for having its own strong intrinsic magnetic field and magnetosphere, which sets it apart from all other moons 38. Ganymede’s mass is about twice that of Earth’s Moon, making it the most massive natural satellite as well .
Titan: Saturn’s Giant Moon
Saturn’s largest moon, Titan, is the second-largest moon in the solar system. Titan is notable for being larger by volume than Mercury and for having a thick atmosphere and an active hydrological cycle involving hydrocarbons 13. Titan’s mass is about half that of Ganymede, but it is still significantly larger than most other moons .
Callisto, Io, and the Moon: Completing the Top Five
Jupiter’s moons Callisto and Io are the third and fourth largest moons in the solar system, respectively. Earth’s Moon ranks as the fifth largest. While our Moon is not the largest by size, it is unique for being very large relative to its parent planet, with a mass that is 1.23% of Earth’s mass—much higher than the relative mass of other large moons to their planets 26.
Triton: Neptune’s Largest Moon
Triton, Neptune’s largest moon, is also among the largest moons in the solar system. It is notable for its relatively large size compared to Neptune and for its geological activity, which is likely driven by tidal heating 16.
Uranus’ Largest Moons
Uranus has five major moons: Miranda, Ariel, Umbriel, Titania, and Oberon. While these are not as large as Ganymede or Titan, they are still significant in size and are being studied for possible subsurface oceans .
Irregular Moons and Other Notable Satellites
Beyond the largest regular moons, the solar system also contains many irregular moons, which are generally smaller and have more eccentric orbits. The largest irregular moons for each of the outer planets are Himalia (Jupiter), Phoebe (Saturn), Sycorax (Uranus), and Triton (Neptune) . These moons are often captured objects rather than having formed in place.
Conclusion
The largest moons in the solar system are Ganymede (Jupiter), Titan (Saturn), Callisto (Jupiter), Io (Jupiter), and the Moon (Earth), with Triton (Neptune) and the major moons of Uranus also being significant. These moons are not only remarkable for their size but also for their unique geological and atmospheric features, making them key targets for ongoing and future exploration 12368910.
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