KRILLIONIO GAME

Space

Name one of Jupiter’s four Galilean moons.

The four large moons first observed by Galileo in 1610.

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Start with the full category, then apply the exact boundary: The four large moons first observed by Galileo in 1610. You only need one qualifying answer. A longer name is not automatically rarer.

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GanymedeGanymede is one of Jupiter’s four Galilean moons, observed by Galileo in 1610.
76

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CallistoCallisto is one of Jupiter’s four Galilean moons, observed by Galileo in 1610.
95
GanymedeGanymede is one of Jupiter’s four Galilean moons, observed by Galileo in 1610.
76
IoIo is one of Jupiter’s four Galilean moons, observed by Galileo in 1610.
46
EuropaEuropa is one of Jupiter’s four Galilean moons, observed by Galileo in 1610.
28

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Each entry belongs to the bounded set defined by the prompt. The named source supports the underlying facts; our editorial scoring is a separate layer.

Source: NASA · Jupiter’s moons

Reference version: 2026-09-13. See our answer policy for how we handle aliases and omissions.

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