Who discovered the four largest moons of Jupiter around 1610?
Moons of Jupiter around Ganymede. In 2016, the "Juno" spacecraft imaged the Galilean moons from above their orbital plane as it approached Jupiter orbit insertion, creating a time-lapse movie of their motion. Moons of Jupiter There are 79 known moons of Jupiter. This gives Jupiter the largest number of moons with reasonably stable orbits of any planet in the Solar System. The most massive of the moons are the four Galilean moons, which were independently discovered in 1610 by Galileo Galilei and Simon Marius and were the first objects found to orbit a body that was neither Earth nor the Sun. From the
Moons of Jupiter that the Voyager space probes reached Jupiter, around 1979, 13 moons had been discovered, not including Themisto, which had been observed in 1975, but was lost until 2000 due to insufficient initial observation data. The Voyager spacecraft discovered an additional three inner moons in 1979: Metis; Adrastea; and Thebe. No additional moons were discovered for two decades, generally during the 1980s and 1990s, but between October 1999 and February 2003, researchers found another 34 moons using sensitive ground-based detectors. These are tiny moons, in long, eccentric, generally retrograde orbits, and averaging in diameter, with the largest being just across. All