Autonoe

Discovery
Autonoe was discovered by Scott S. Sheppard, David C. Jewitt and Jan T. Kleyna at the Mauna Kea Observatory in Hawaii on 10th December 2001.

In-Depth
Autonoe is considered a member of the Pasiphae group, a family of Jovian satellites which have similar orbits and therefore must have a similar origin.

Most or all of the Pasiphae satellites are thought to have begun as a single asteroid that, after being captured by Jupiter's gravity, suffered a collision and broke off a number of pieces. The bulk of the original survived which is named Pasiphae and some or all of the pieces that broke off became members of group.

All of the Pasiphae moons are retrograde, they orbit Jupiter in the opposite direction of the parent planet's rotation. Their orbits are also eccentric (elliptical rather than circular) and highly inclined with respect to Jupiter's equatorial plane. These characteristics support the idea that the Pasiphae satellites began as one or more captured as asteroids, rather than forming as part of Jupiter's original system.

Compared to other Jovian satellites, scientists have lost confidence that the Pasiphae moons originated in a single collision. This is due to differences in each moon (varying from red to grey), differences in orbital eccentricity and inclination among the other member of the Pasiphae group. Sinope, in particular, is suspected to have started out as a single asteroid.

If Sinope does not belong in the Pasiphae group, then the individual moon named Pasiphae still retain 99% of the mass from the original asteroid. If Sinope is included, Pasiphae still retain 87% of the original mass. None of the Pasiphae members are strong enough to pull themselves into a sphere, so they're probably irregularly shaped.

Autonoe has a mean radius of 1.2 miles (2 kilometres), assuming an albedo of 0.04. The satellite takes 761 Earth days to complete one orbit, with an average distance of 14.9 million miles (24 million kilometres) from Jupiter.

Namesake
Originally designated S/2001 J1, Autonoe was named after the mother of Graces by Jupiter, according to various authors.

A moon ending in "e" was chosen when it was discovered since it's located in the outer system of Jovian satellites.