Jupiter Dethrones Saturn As the Planet With the Most Moons

As in mythology, Jupiter has supplanted Saturn for another grand title.

Astronomers recently reported that Jupiter now has more moons than Saturn, wresting the title of "the planet with the most moons" from the Ringed Planet after many years.

NASA mentioned that Saturn has 83 moons, with 63 of them being confirmed and named, while the remaining 20 are awaiting confirmation of discovery and official naming.

Jupiter New Moon Count Details

Astronomers from the Minor Planet Center (MPC) of the Smithsonian Astrophysical Observatory released a new report stating that they discovered 12 new moons are orbiting Jupiter, per Sky and Telescope.

It is important to remember that NASA stated that the king of the planets has between 80 and 92 moons, but neither number captures "the complexity of the Jovian system of moons, rings, and asteroids."

However, according to Scott Sheppard, the astronomer who recently submitted observations of Jupiter and his system of moons from 2021 and 2022, the discovery of these moons definitively puts Jupiter's moon count to a solid 92, overtaking Saturn's 83.

According to the MPC's report, all newly discovered moons are small and outliers of Jupiter's many moons, with them taking more than 340 days to orbit the Gas Giant. Additionally, nine of the 12 newly discovered moons are among the 71 outermost Jovian moons, which take more than 550 days to complete a full revolution around Jupiter.

Jupiter probably captured these moons opposite in direction to the inner moons, as evidenced by their retrograde orbits.

Additionally, five of the moons are larger than eight kilometers, and that three of them are in among 13 others that orbit in a prograde direction.

For those unaware, NASA defined retrograde as the direction opposite of other bodies within a system, while prograde is the direction that most bodies follow.

These three moons are thought to have formed where they are, with them lying between the large, close-in Galilien moons such as Io, Europa, and Ganymede, and the far-out retrograde moons.

However, Sheppard mentioned that these new moons are harder to find since they are closer to Jupiter, with the planet's scattered light obscuring them in the sky and from astronomers' telescopes.

Interestingly, Sheppard mentioned that five moons were found before 2000, while eight more were discovered since then.

The Contest Of Moons

Unlike mythology, however, Jupiter may be unable to hold unto its new title soon. According to Space.com, astronomers also found tons of rocks down to about three kilometers wide around Saturn without precisely tracking them.

With astronomical instruments becoming more and more capable of studying these smaller moons, it is only a matter of time before Jupiter would be forced to relinquish its new title back to Saturn.

Regardless of the title, the discovery of these new moons makes them a great target for future Jupiter flyby missions to see them up close, such as the European Space Agency's JUICE mission and NASA's Europa Clipper, which are set to launch in April 2023 and Oct. 2024, respectively.