Noun
Galilean satellites pl (plural only)
(astronomy) The four Galilean moons of Jupiter.
The Jovian subnebula may have been relatively "gas-starved" when the Galilean satellites formed; this would have allowed for the lengthy accretion times required for Callisto. Source: Internet
The three inner Galilean satellites are in a resonance with one another such that whenever two of them are aligned, the third will always be non-aligned and quite often situated on the opposite side of Jupiter. Source: Internet