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Why doesn't Jupiter have rings around its planet?

It's a question that's long baffled space experts ... until now!

As the largest planet in the solar system, Jupiter ought to have bigger and more spectacular rings than Saturn, which is smaller.

But new research suggests that the gas giant's large moons destroy any rings before they have a chance to form!

Researchers at the University of California in America carried out a computer simulation which looked at the orbits of Jupiter's four main moons, as well as the orbit of the planet, and information about the time it takes for rings to form.

"It's long bothered me why Jupiter doesn't have even more amazing rings that would put Saturn's to shame," said Professor Stephen Kane, who led the research.

"If Jupiter did have them, they'd appear even brighter to us, because the planet is so much closer than Saturn."

Saturn's rings are largely made of ice. The team say that if the moons are large enough, their gravity can toss the ice out of a planet's orbit, or it can change the orbit of the ice enough so that it collides with the moons.

Large planets such as Jupiter form large moons, which prevents them from having significant rings.

"We found that the Galilean moons of Jupiter, one of which is the largest moon in our solar system, would very quickly destroy any large rings that might form," Professor Kane said.

Therefore it is unlikely that Jupiter had large rings at any point in its past.