Pallene (pronounced pal-lee-nee, adjective: Pallenean) is a tiny 4-km (3-mile) diameter moon that orbits between Mimas and Enceladus at about 211,000 km (131,000 miles) from Saturn. Scientists have two theories to explain the presence of Pallene and two other tiny sister moons, Methone and Anthe. First, the three moons may have split from either Mimas or Enceladus. Second, all five moons may be the remains of a larger swarm that traveled in that area close to Saturn.
Pallene circles Saturn in approximately 27.7 hours. Because Pallene and its two sister moons orbit at very similar distances from Saturn, they are in a dynamical relationship. Mimas strongly perturbs Pallene, the 3-km (2-mile) diameter moon Methone and the 2-km (1-mile) diameter moon Anthe, all of which orbit between Mimas and the next major moon, Enceladus. The vastly more massive Mimas causes the orbits of the tiny moons to vary by as much as 20 km (12.4 miles).
These three moons may also be contributing particles to Saturn's E-ring. The moons are small and were only recently discovered. Consequently, astronomers have few details on characteristics of these moons such as reflectivity (albedo), rotation (probably tidally locked on Saturn because they are so close) and composition.
The Cassini Imaging team discovered Pallene on 1 June 2004. Pallene and nearby Methone were the first moons discovered in Cassini images.
How Pallene Got its Name:
John Herschel suggested that the moons of Saturn be associated with the mythical brothers and sisters of Kronus. (Kronus is the equivalent of the Roman god Saturn in Greek mythology.) The International Astronomical Union now controls the official naming of astronomical bodies.
The name Pallene comes from the name in Greek mythology of one of seven Alkyonides -- daughters of the god (or Titan) Alkyoneus. Alkyoneus sprang from Gaea and the blood of Uranus. This blood was spilled when Uranus' son -- and Alkyoneus' brother -- Kronus castrated his father. Herakles (Hercules) killed Alkyoneus in the war between the gods of Mount Olympus and the Titans. Overcome by grief, the seven daughters threw themselves into the sea to die, but the goddess Amphitrite took pity on them and transformed them into halcyons or kingfishers.
Astronomers also refer to Pallene as Saturn XXXIII and as S/2004 S2. Pallene has been determined to be the same object spotted in a single image taken by NASA's Voyager spacecraft in the 1980s, at that time known as S/1981 S14.