Jupiter now has 92 moons — more than any other planet in our solar system

Astronomers have discovered 12 new moons around Jupiter, putting the total count at a record-breaking 92. That's more than any other planet in our solar system.

Giant planet breaks Saturn's record after astronomers spot 12 new moons in orbit

An image of a large planet with several small moons around it.
This image provided by NASA shows a false colour composite image of Jupiter obtained by the James Webb Space Telescope on July 27, 2022. The planet's rings and some of its small satellites are visible along with background galaxies. (NASA/The Associated Press)

Astronomers have discovered 12 new moons around Jupiter, putting the total count at a record-breaking 92. That's more than any other planet in our solar system.

Saturn, the one-time leader, comes in a close second with 83 confirmed moons.

The Jupiter moons were added recently to a list kept by the International Astronomical Union's Minor Planet Center, said Scott Sheppard of the Carnegie Institution, who was part of the team.

They were discovered using telescopes in Hawaii and Chile in 2021 and 2022, and their orbits were confirmed with follow-up observations. These newest moons range in size from 1 kilometre to 3 kilometres, according to Sheppard.

This sky map shows the positions of four of Jupiter's moons the following night of the opposition, on Sept. 27, 2022, at roughly 10:30 p.m. ET. (Stellarium)

"I hope we can image one of these outer moons close-up in the near future to better determine their origins," he said in an email Friday.

In April, the European Space Agency is sending a spacecraft to Jupiter to study the planet and some of its biggest, icy moons. And next year, NASA will launch the Europa Clipper to explore Jupiter's moon of the same name, which could harbour an ocean beneath its frozen crust.

People stand in a warehouse below a large grey box-like structure with a round satellite mounted on the front.
The ESA's (European Space Agency) 'Juice' probe is unveiled for media in Toulouse, France, on January 20, 2023, a few days ahead of its departure to Kourou space centre. Scheduled for launch in April 2023, Juice will make detailed observations of Jupiter and its three large ocean-bearing moons Ganymede, Callisto and Europa with a suite of instruments. (Charly Triballeau/AFP via Getty Images)

Sheppard — who discovered a slew of moons around Saturn a few years ago and has taken part in 70 moon discoveries so far around Jupiter — expects to keep adding to the lunar tally of both gas giants.

Jupiter and Saturn are loaded with small moons, believed to be fragments of once bigger moons that collided with one another or with comets or asteroids, Sheppard said.

The same goes for Uranus and Neptune, but they're so distant that it makes moon-spotting even harder. Uranus has 27 confirmed moons, Neptune has 14, Mars has two, and Earth has one moon. Venus and Mercury come up empty.

Jupiter's newly discovered moons have yet to be named. Sheppard said only half of them are big enough — at least 1.5 kilometres or so — to warrant a name.

A moon passing by the planet Jupiter in the background.
Gliding past the planet Jupiter, the Cassini spacecraft captures this awe inspiring view of active Io, Jupiter's third largest satellite, with the largest gas giant as a backdrop, offering a stunning demonstration of the ruling planet's relative size, April 20, 2001. (NASA/Getty Images)


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