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How are Jupiter’s regular moons different from its irregular moons?
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Jupiter
Photograph of Jupiter taken by Voyager 1 on February 1, 1979, at a range of 32.7 million km (20.3 million miles). Prominent are the planet's pastel-shaded cloud bands and Great Red Spot (lower centre).
Jupiter’s moons are categorized into two groups based on their orbital characteristics:
- Regular Moons: These are the inner eight moons, including the four Galilean satellites (Io, Europa, Ganymede, and Callisto). They are defined by their nearly circular orbits that lie within the plane of the planet’s equator, characterized by low orbital inclinations and low eccentricities.1
- Irregular Moons: These are the numerous moons found beyond the orbit of Callisto. Unlike the regular moons, they possess orbits with much higher inclinations and eccentricities. Many of these small, fragmented bodies are believed to have been captured by Jupiter and can be classified into groups based on their specific orbital paths, which include both prograde and retrograde motion.12