Jupiter overtakes Saturn to have most moons in the solar system
Jupiter has overtaken Saturn to have the largest family of moons in the solar system – perhaps fittingly for the biggest planet.
Astronomer Scott Sheppard and his team at Carnegie Institution for Science in Washington D.C. found 12 previously unreported Jupiter moons – taking the total to 92.
Sheppard said more discoveries are expected to be made.
Saturn, the one-time leader, now comes in a close second with 83 confirmed moons.
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The Jupiter moons were added recently to a list kept by the International Astronomical Union's Minor Planet Center.
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 0.6 miles to two miles wide, according to Sheppard.
He said: "I hope we can image one of these outer moons close-up in the near future to better determine their origins."
In April, the European Space Agency (ESA) is sending a spacecraft to study Jupiter and some of its biggest, icy moons – Ganymede, Callisto and Europa.
Next year, Nasa is leading the Europa Clipper mission to explore Europa, one of the many moons orbiting the planet.
And Nasa's Dragonfly mission team will send a rotorcraft in 2027 to Saturn's largest moon, Titan.
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.
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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 14, Mars two and Earth one. 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 one-mile-wide or so – to warrant a name.
Watch: Alan Shepard walks on the moon in 1971