20 new moons of Saturn discovered

20 new moons of Saturn discovered

Previously, Jupiter held the title for having the most number of moons in the solar system with a total count of 79.

Sheppard says he thinks Saturn probably has 100 moons that are a kilometre in size or bigger, but astronomers may need to wait for the next generation of bigger, better telescopes to confirm them all. Seventeen of them have retrograde orbits, meaning they move around Saturn in the opposite direction to the planet's rotation.

The new moons were discovered by a team of scientists from Carnegie Science, University of California Los Angeles (UCLA) and the University of Hawaii, using the Subaru Telescope on Hawaii.

They are all much farther out from the planet than the other known moons, such as Titan and Enceladus, and they are split into three separate groups.

"Using some of the largest telescopes in the world, we are now completing the inventory of small moons around the giant planets", said Dr Sheppard.

The new moons were slotted into three distinct categories depending on the angles at which they orbit around Saturn.

The Carnegie Institution for Science has now launched a public moon-naming competition for the newly discovered moons.

The more-distant retrograde moons and one of the prograde moons are further out, each taking more than three years to complete an orbit.

The team says that the orbits of these new moons make it possible to narrow down a window for when they formed. The two innermost prograde objects align with the "Inuit group", and the outermost prograde moon among the new finds may belong to the "Gallic group", but that's unclear at the moment, researchers said. The retrograde moons join the Norse group (all named after Norse mythology), while two others join the Inuit group (named for Inuit mythology), and the final moon goes with the Gallic group (again, mythology). Another is planned for Saturn's mini moons. Even though it orbits among a bunch of Norse group moons, its oddball behaviour puts it as part of the "Gaelic" group.

"This kind of grouping of outer moons is also seen around Jupiter, indicating violent collisions occurred between moons in the Saturnian system or with outside objects such as passing asteroids or comets", Sheppard said.

Studying the orbits of these moons helps researchers reconstruct Saturn's past.

These baby moons may have come from larger parent moons that broke apart right after Saturn formed.

At the birth of the solar system, vast amounts of dust and gas circling the sun coalesced into the eight known planets. During that time, a cloud of gas and dust surrounded the planet.

Similar to their discovery of a dozen moons orbiting Jupiter past year, the team will now host a public contest created to name the newest additions to Saturn's bevy of moons.

The team of scientists have also tried to categorize the moons by their inclinations; they can broadly be classified into three different clusters: the Inuit, Norse, and Gallic groups.

These are the discovery images for the newly found very distant prograde moon of Saturn.

You can't submit just any name though. The contest opened Monday and will last for two months.

In fact, Jupiter has held the "moon king" title for decades, and got a dozen new moons added to its tally just a year ago, says Scott Sheppard, the Carnegie astronomer who led the new discoveries.



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