Final answer:
Mars has only two moons, while Jupiter has a substantial 79 known moons, reflecting the significant difference in the number of moons inner planets have compared to outer planets. The moons of outer planets are diverse in composition, often made of ice or rock-ice mixtures, and vary greatly in size and orbit.
Step-by-step explanation:
The moons of the inner planets differ significantly in number compared to those of the outer planets. Mars, which is an inner planet, has two moons named Phobos and Deimos. In stark contrast, Jupiter, an outer planet, boasts a much larger number of moons, with a current known total of 79. These numbers exemplify the considerable discrepancies between the inner and outer planet moon counts.
Jupiter's moons, including the four large ones known as the Galilean moons – Callisto, Ganymede, Europa, and Io – display a richness in diversity and size. Ganymede actually stands as the largest moon in the solar system, being larger even than Mercury. Most of Jupiter's moons are much smaller and many are in retrograde orbits far from the planet. The composition of moons around the outer planets varies, ranging from icy bodies to rock-ice mixtures, differing from our Moon that is primarily composed of rocky material.
The outer solar system's moons, with nearly 200 known moons, are too numerous to discuss in detail. While additional small moons are anticipated to be discovered, our understanding of their precise nature will undoubtedly evolve in future. The giant planets all possess rings as well, adding to the complexity of their moon systems.