Jupiter's moons

Jupiter's moons were the first moons to be discovered in the Solar system, since Luna, Planet Earth's moon.

Galileo was an early experimenter with telescopy, and is the first person to write about using a telescope to study the sky. He discovered the largest of Jupiter's moons -- all roughly comparable in size to Luna. He merely numbered them, but they were later named after individuals from Roman mythology, specifically they are named after four of the god Jupiter's lovers. Ganymede, the largest moon, is named after one of Jupiter's male concubines.