Solar System -
There are two named moons of Jupiter that do not fit into any of the Groups. They are Carpo and Themisto.
A small, prograde moon, about 3 km (1.9 miles) in diameter, Carpo orbits Jupiter at a distance of 17.1 million km (about 10 million miles) every 458.625 days. Its orbit, just beyond that of the Himalia Group, is highly eccentric. It is the last prograde moon in Jupiter orbit; all the moons further out orbit in a retrograde direction. Carpo was discovered in 2003. Carpo was one of the daughters of Zeus/Jupiter.
Themisto is a prograde moon, somewhat larger than Carpo at about 8 km (5 miles) in diameter. It orbits Jupiter at a distance of 7.4 million km (4.6 million miles) every 129.83 days. The orbit is outside of the Galilean moon orbits, and inside the Himalia Group of moons. It was discovered in 1975, and then lost due to there not having been enough observations to establish its orbit. Luckily, it was re-discovered in 2000. Themisto was one of Zeus' lovers.
Valetudo is another prograde moon, somewhat smaller than Carpo at about 1 km (0.6 miles) in diameter. Its discovery was announced in2018. It orbits Jupiter at a distance of 19 million km (12 million miles) every 533.3 days. It crosses the paths of a number of retrograde moons, and may collide with them in the future. The moon is named after the Roman goddess of health and hygiene who was a great-granddaughter of Jupiter[.
Jupiter's moons are grouped as follows. Select to see details of the moon or the group of moons: