 The planet Saturn is seen from the Cassini spacecraft on July 23, 2008. Twenty new moons have been found around Saturn, giving the ringed planet a total of 82, scientists said Monday. (NASA/JPL/Space Science Institute via AP) | | | Okay. The first thing I need to say is, the planets are not in a contest. (And if they were, Jupiter would win.) With that out of the way, I'm pleased to inform you that scientists have just discovered a whopping 20 new moons in orbit around Saturn, raising the ringed planet's moon count to a total of 82. That's three more than Jupiter's 79 moons. Each of the newfound bodies is about three miles wide — roughly the size of Nauru, the world's smallest island nation. All but three of them are retrograde, meaning they orbit Saturn in the opposite direction to the one the planet rotates around its own axis (the motion of the remaining three is called "prograde"). They appear to be grouped in clusters, according to Scott Sheppard, the Carnegie Institution astronomer who led the team that made the discoveries. This suggests they were born in violent collisions between larger moons or with passing asteroids and comets sometime after the Saturnian system formed, Sheppard said. The worlds were discovered using one of Earth's largest telescopes, perched atop a volcanic mountain in Hawaii. Now all they need is names. But the International Astronomical Union, which has served as the official arbiter for planetary and satellite nomenclature for 100 years, has some very stringent guidelines for new moon christenings. Two of the prograde moons belong to a cluster of Saturnian satellites called the Inuit group, and must be named for giants from Inuit mythology. The other prograde moon is a bit of an outlier, but since its orbit most closely resembles that of moons in the Gallic group, it must be named for a giant from the myths of Iron Age France. All the retrograde orbiters, which fit into the Norse group, should be named for — you guessed it — Norse giants. Why so many giants, you may ask? Astronomer John Herschel, the son of the man who discovered two of Saturn's moons, started the tradition of naming Saturnian satellites after Titans in the 19th century. When the IAU ran out of names from Greek mythology (82 moons is, after all, a lot) they moved on to giants from other traditions. Carnegie is taking suggestions for names, so if you've got an idea, you can tweet it at the handle @SaturnLunacy with the hashtag #NameSaturnsMoons. And tag me (@sarahkaplan48) — I'd love to see what ideas Speaking of Science readers come up with! — Sarah | 
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